Melag melaquick 12 ошибки

Chapter 9 – Malfunctions

Chapter 9 – Malfunctions

In this chapter you learn



Which type of messages exist



How to react to errors



What you can do before calling the hotline



What you can do if no display appears



What you can do in case of poor drying results

Danger of infection!

Warning messages

Warning messages are displayed when necessary. Warning messages

are not malfunction messages. They help to ensure malfunction-free

operation and to recognize undesirable situations. Observe these

warnings early in order to avoid malfunctions.

Malfunction message

Malfunction messages are displayed if safe operation or sterilization safety

is not guaranteed.

These can appear on the →display shortly after switching on the steam

sterilizer or while a program is running.

If a malfunction occurs during a program run, the program will be

interrupted.

■

If a program is discontinued during the sterilization phase, the load is

unsterile. Repackage and repeat the sterilization for the respective →

items to be sterilized, as needed.

Failure to observe these provisions can endanger the health of your

patients and practice team.

The error message is then shown on the display in alternation with the

current program phase. After the program abort or termination, the error

message is shown on the display in alternation with the message

Acknowledge with button «-» and Program stopped. In order to

delete the error message, press the K

Before you call

Follow the operating procedures shown in connection with a warning text

or an malfunction message on the →display of the steam sterilizer. You

will find the most important events in the following table. Possible causes

and appropriate operating instructions are listed for the events.

(-).

EY

49

 
 
 
since fabr. no. 94 12 5000    subject to technical alterations 
 
 
User Manual 
 
Fast-action Autoclave 
 
MELAquick
®
12 
 
 
 
 
Dear Doctor: 
Thank you very much for the trust which you have shown by purchasing this autoclave. 
For more than 55 years now, MELAG — a medium-sized family-owned and -operated 
business — has specialized in the production of sterilization equipment for medical prac-
tice. During this period, MELAG has succeeded in becoming a leading manufacturer of 
sterilization equipment. More than 420,000 MELAG units sold throughout the world testify 
to the exceptional quality of our sterilizers. 
As all other MELAG products, this autoclave was manufactured and tested according to 
strict quality criteria. Before placing this unit into operation, please thoroughly read this 
Operating Manual. The long-term functional effectiveness and the preservation of the 
value of your autoclave will primarily depend on careful preparation of instruments before 
sterilization, and on proper care of the unit. 
The management and staff of MELAG 
 
 





 
 
page 2 
 
The functional effectiveness and the preservation 
of value of this unit depend on: 
1. Proper preparation of the instruments to be sterilized 
2. Proper care of the autoclave 
3. The use of sufficiently pure distilled / demineralized water 
IMPORTANT! Be sure to observe the safety instructions on page 13! 
In the event that your autoclave should not function properly, first read the instructions beginning on page 22 
before you notify the MELAG Customer Service Department. 
Please note down here the factories number of your device in case you need to identify it for our Customer 
Service Department. This number is on the rear side of the unit. Type 12 factory no.  .................... 
  page 
   
1  Description of the autoclave......................................................................................4 
1.1  View of the apparatus.................................................................................................4 
1.1.1  Front view.....................................................................................................................4 
1.1.2  Rear View.....................................................................................................................5 
1.1.3  Sectional view - for service only...................................................................................6 
1.2  Technical data ............................................................................................................7 
1.3  Operating scope for sterilization and disinfection .......................................................7 
1.4  Electronic-parametric regulation.................................................................................7 
1.5  Printout of the log........................................................................................................8 
1.6  Water-one-way system...............................................................................................8 
1.7  No start of program if water quality is inadequate ......................................................8 
2  Introduction ...............................................................................................................9 
2.1  Preparation of instruments..........................................................................................9 
2.2  Formation of rust = foreign rust...................................................................................9 
2.3  Cleaning and care of the autoclave ............................................................................9 
2.4  Testing the function of the autoclave........................................................................10 
3  Installation...............................................................................................................11 
3.1  Positioning the autoclave..........................................................................................11 
3.2  Connection of water discharge .................................................................................11 
3.3  Filling the water reservoir..........................................................................................12 
3.4  Connection of the logging printer..............................................................................12 
3.5  Setting the time of day and the date.........................................................................12 
3.6  Empty sterilization process.......................................................................................12 
3.7  VDE-requirements ....................................................................................................13 
3.8  Safety precautions....................................................................................................13 
4  For every sterilization / disinfection cycle ................................................................14 
4.1  Main switch, pre-heating of the vessel......................................................................14 
4.2  Selection of program.................................................................................................14 
4.3  Items to be sterilized.................................................................................................14 
4.4  Preparation of instruments........................................................................................15 
4.5  Loading.....................................................................................................................15 
4.6  Starting the sterilization / disinfection .......................................................................15 
4.7  Automatic pressure release......................................................................................15 
4.8  Automatic printout of the log.....................................................................................16 
4.9  Successful end of a process.....................................................................................16 
4.10  Removal of instruments............................................................................................16 
4.11  Drying .......................................................................................................................16 
4.12  Particuliarities of the disinfection ..............................................................................16 
4.13  Overheat protection ..................................................................................................16 
4.14  Process control.........................................................................................................17 
4.15  Sterilizing frequency .................................................................................................17 
5  Further informations about sterilization ...................................................................17 





 
User Manual 
MELAquick
®
12
 
page 3 
5.1  Total operating time..................................................................................................17 
5.2  Accuracy of process regulation.................................................................................19 
5.3  Use of aqua dest / aqua dem....................................................................................19 
5.3.1  Amount of consumption .............................................................................................20 
5.3.2  Emptying the reservoir ...............................................................................................20 
5.3.3  Refilling / Replacement..............................................................................................20 
6  Putting out of operation / Transport.........................................................................21 
6.1  Transport under danger of frost................................................................................21 
7  Breakdowns without warning light ...........................................................................22 
7.1  No Indication or false indication of the operating state.............................................22 
7.2  Lamp 
„
READY“ does not light continuously..............................................................22 
7.3  Impossible to start a program ...................................................................................22 
7.4  The water pump does not start when the program begins .......................................23 
7.5  Too small indication of pressure and/or temperature ...............................................23 
7.6  Excessive indication of pressure and/or temperature...............................................23 
7.7  Hissing during run / foggy instruments .....................................................................23 
7.8  Sliding door cannot be unlocked...............................................................................24 
7.9  The sliding door cannot be easily moved .................................................................24 
7.10  Water reservoir goes empty......................................................................................24 
8  Fault with warning light............................................................................................25 
8.1  Fault No. 1 ................................................................................................................25 
8.2  Fault No. 4 ................................................................................................................26 
8.2.1  Autoclave insufficiently ventilated ..............................................................................26 
8.2.2  Pressure switch is wrongly adjusted/defective ..........................................................26 
8.2.3  Failure of the heating for steam generation...............................................................26 
8.2.4  Short circuit of the temperature sensor for steam......................................................27 
8.2.5  Too small dose of water.............................................................................................27 
8.2.6  Too much loss of water..............................................................................................27 
8.2.7  Steam generator is clogged with boiler scale ............................................................28 
8.3  Fault No. 5 ................................................................................................................28 
8.3.1  The amount of water measured out is not sufficient / loss of water...........................28 
8.3.2  Interchange the temperature sensors........................................................................28 
8.4  Fault No. 9 ................................................................................................................28 
8.5  Fault No. 11 ..............................................................................................................29 
8.6  Fault No. 12 ..............................................................................................................29 
8.7  Fault No. 15 ..............................................................................................................30 
9  Spare parts..............................................................................................................31 





 
 
page 4 
1  Description of the autoclave 
1.1  View of the apparatus ____________________________________________________  
1.1.1 Front view _____________________________________________________________________ 
 
1  Sliding door    9  Door is open  16  Sterilization mode 
2 Locking handle  10 
„
Fault“ 17 Disinfection mode 
3 Water reservoir  11 
„
Ready“ 18 Hose connector 
4 
„
Main“ switch  12 
„
Running“ cycle  19  Water tank drain 
5 Pressure gauge  13 
„
End“ of cycle  20  Power Supply for MELAprint
®
40 
6 Thermometer  14 
„
Main“ on  21  Interface for MELAprint
®
40 
7  Start button  15  Program selector switch  22  Waste water hose 
8 Insufficient water    Sterilization/Disinfection 23 Condenser container 





 
User Manual 
MELAquick
®
12
 
page 5 
1.1.2 Rear View______________________________________________________________________ 
 
 
underneath 





 
 
page 6 
1.1.3  Sectional view - for service only ___________________________________________________ 
 
 
31  Fuses  39  Temperature sensor thermometer  47  Feed pump with thermal protection 
32  Output test button (and others)  40  Measuring block with fine filter  48  Lithium battery 
33  Overheat protection for steam gen-
erator 
41  Steam filter in front of solenoid valve  49  Solenoid valve for pressure release 
34  Temperature sensor pre-heating  42  Safety valve  50  Micro switch for door lock 
35  Temperature sensor steam  43  Current jet (below hose connector)  51  Overheat protection for pre-heating 
36  Base plate  44  Steam filter in front of measuring block 52  Water reservoir 
37  Vessel-block  45  Water level switch  53  Pressure-switch for sterilization 
38  Steam generator  46  Water filter  54  Pressure-switch for disinfection 





 
User Manual 
MELAquick
®
12
 
page 7 
1.2 Technical data __________________________________________________________  
Type 12   
Sterilization chamber (diameter x height)  9 cm × 16 cm 
Required power-connection ratings:  1100 W, 230 V, AC 
Average consumption  400 W with 4 Sterilizations per hour 
Power costs per sterilization cycle (at y €/kWh)  = y €/kWh x 0,1 kWh 
(incl. preheating phase, on basis of 8-hour operation with 4 sterilization cycles/h) 
Power costs per disinfection cycle 
(at y €/kWh)  = y €/kWh x 0,068 kWh 
(incl. preheating phase, on basis of 8-hour operation with 4 disinfection cycles/h) 
Sterilization: pressure / temperature 
2 bar (134
{
C) -2.1 bar (135
{
C)  
maximum load  1 kg  (incl. basket etc., no textiles) 
Disinfection: pressure / temperature 
0.2 bar (105 
{
C) - 0.3 bar (107
{
C)  
maximum load (only unpacked)  1 kg  (incl. basket etc., no textiles) 
 . 
1.3  Operating scope for sterilization and disinfection _____________________________  
This autoclave is designed for quick sterilization. All  
instruments must be sterilized if the possibility has 
existed that it could possibly have come into contact 
with even the smallest amount of blood during its 
use. There is only one case a disinfection should 
substitutely be used and that is if the composi-
tion of the material does not allow a sterilization. 
Especially older hand pieces and turbines whose 
light conductors can be damaged by repeated steri-
lization, can be disinfected under steam pressure 
to ensure at least the disinfection of inner parts. 
The 
„
SELECT“ button (15) is located on the control 
panel. The operator uses this button to select the 
sterilization or disinfection program. Signal lamps 
(16 and 17) indicate the program. Before leaving the 
factory, the autoclave is set to 
„
sterilization“. 
The operator should select the desired program as 
soon as possible after switching on the electrical 
power switch 
„
MAIN“ (4). If the autoclave has been 
already preheated (the 
„
READY“ lamp (11) glows), 
and  if the program is only then switched from 
„
Disinfection“ to 
„
Sterilization“, the autoclave will 
run through a brief reheating phase of about 5 min-
utes. If the program is switched from 
„
Sterilization“ to 
„
Disinfection“ after preheating, then the autoclave 
will run through a cool-down phase for the pres-
sure vessel, of up to 45 minutes (see Section 4.2.). 
during this reheating or cool-down phase, the 
„
READY“ lamp (11) will flash, and the autoclave 
cannot be put into operation. 
Important! 
• Items for sterilization can also be sealed into 
transparent sterilization packages. 
• Steam pressure disinfection is permissible only for 
instruments which are unpacked. 
• This autoclave cannot disinfect or sterilize liquids 
or textiles. 
• Observe the instructions above on the reheating 
and cool-down phase if the program is changed 
between sterilization and disinfection after the 
autoclave has been preheated. 
1.4 Electronic-parametric regulation ___________________________________________  
All autoclaves of type 12 are equipped with an elec-
tronic regulator. With the implement of microproc-
essors it is now possible to control the parameters 
pressure and temperature and keep their values 
constant during sterilization or disinfection. This con-
trol is called electronic-parametric regulation.  
The ideal processing time can be adapted according 
to load and temperature of the vessel. The systems 
which control the sterilization and disinfection proc-
esses with respect to limit temperatures and pres-
sure, and the timed sequences associated with 
these variables, consequently ensure as well the re-
liability of the sterilization and disinfection results. 
 
 





 
 
page 8 
1.5  Printout of the log _______________________________________________________  
The autoclave has a serial interface jack (21) for 
connection of the logging printer MELAprint 40
®
 (or-
der no. 289). Power is also provided to the  
MELAprint 40
®
 through another connection (20) from 
the autoclave. 
When the printer is connected, a log containing the 
process-relevant parameters will be automatically 
printed out after each sterilization or disinfection cy-
cle (see example of log at the right). 
It is normal here that time metering will be briefly in-
terrupted once or several times during the first sec-
onds after beginning of the sterilization period, dur-
ing heating of the pressure vessel up to sterilization 
temperature. 
At the bottom of the printout there is a line without 
explain text with service information. 
In addition, the last log to be printed out is always 
permanently stored in the system memory (even if 
power fails). To print out the last log again, press the 
„
SELECT“ button (15) and hold it down for at least 
3 seconds. 
In the case of a fault, a log will also be printed out to 
indicate the time, the temperature, and the cause of 
the fault. Section 8 below contains a list of the fault 
numbers and their meanings. 
1.6 Water-one-way system ___________________________________________________  
A normal circulating water system, used in most 
autoclaves where the steam is condensed in the wa-
ter reservoir again, has an important disadvantage. 
The instruments must be absolutely free from dirt 
and chemicals before sterilization/disinfection, oth-
erwise not only the autoclave but also the in-
struments will be damaged and become dirty. How-
ever, in daily practice, the instruments are prepared 
insufficiently. This is critical especially for the sterili-
zation of turbines and contra-angles which have to 
be oiled before sterilization. Oil, dirt and other 
chemicals are getting into the apparatus and will 
stay there because of the circulating system. This 
can lead to spotty corrosive instruments and often to 
a failure of the autoclave. 
For this reason the MELAquick 12
®  
uses the 
one-way system: all water and steam used for 
the process, is discharged into a waste water 
container (23). 
 
1.7  No start of program if water quality is inadequate _____________________________  
You have purchased a high-quality German auto-
clave product. It is designed to ensure a long life of 
service, even if the operator makes certain mis-
takes. For this reason, the MELAquick 12
® 
 has an 
automatic warning system which prevents it from be-
ing operated if, for example, the operator forgets to 
use distilled water and fills it with normal tap water 
(which would damage it by the formation of boiler 
scale). The MELAquick 12
® 
 must be filled with dis-
tilled or demineralized water (aqua dest / dem) in 
accordance with DIN/EN 13060 or VDE 0510. 
Please see Section 5.3 on details on water quality 
and on the suppliers of the required water. 
In order to prevent the instruments or the autoclave 
from being damaged from formation of boiler scale 
or corrosion, the autoclave has an integrated system 
for testing of the quality of the water in the tank (con-
ductivity): 
During the first 2 seconds after start of the cycle, the 
autoclave automatically tests the quality of the water 
in the water storage tank (52). If the water quality is 
somewhat poorer than specified in DIN EN 13060, 
but is still sufficiently good, then the lamp 
„
WATER“ (9) will flash to warn the operator. The 
program continues to run, however. If the water 
quality is not adequate, the lamp 
„
WATER“ (9) will 
flash, and the lamp 
„
FAULT“ (10) will glow. In 
such case, in order to protect the instruments and 
the autoclave, the program will not start. The opera-
tor must replace the water in the tank by better (for 
example, demineralzed) water and press the 
„
START“ (7) button again.
 
------------------------------------------ 
MELAquick  12 
------------------------------------------ 
Date      :                   23.09.1994 
Time      :                   10:37  
Charge No.:                   4 
------------------------------------------ 
Program  : 
Sterilization   134°C 
------------------------------------------ 
Program step            Temp.     Time   
                        [°C]    hh:mm:ss 
Preheat Temperaure      132     10:37:39 
Start                   122     10:37:39 
Sterilization start     134     10:39:25 
Sterilization stop      134     10:39:27 
Sterilization runs      134     10:39:27 
Sterilization end       135     10:43:26 
End of program          127     10:43:56 
------------------------------------------ 
Program has run 
succesfully ! 
------------------------------------------ 
Sterilization time :    04 min 00 s 
Sterilization temp.:  MIN 134°C, MAX 135°C 
total Time         :    06 min 17 s 
------------------------------------------ 
8  2 09940933 3.22 C1 V1 DS1 PS0 





 
User Manual 
MELAquick
®
12
 
page 9 
2 Introduction 
2.1  Preparation of instruments ________________________________________________  
MELAG - rust-proof materials 
All parts of the MELAquick 12
® 
 autoclave which 
come into contact with steam are made of rustproof 
materials: the pressure vessel of coated aluminium, 
the pressure vessel door and steam generator of 
stainless steel, pressure lines of Teflon, and 
threaded connectors and valves of brass. 
Foreign rust 
The use of non-corrosive materials prevents rust in 
the autoclave. It is proven that the possible appear-
ance of rust is caused by rust of foreign instruments. 
Formation of rust can even appear on stainless steel 
by inappropriate treatment of the instruments with 
chemicals and disinfection methods during prepara-
tion. 
Preparation of instruments to be sterilized 
You see the importance of correct and careful 
preparation before sterilization, which shall be 
stressed here once again. 
Turbines and contra-angles must be cleaned and 
oiled according to the manufacturer´s instructions. 
Immediately after use, all other instruments must be 
disinfected by being placed in a disinfectant solution, 
and must be cleaned, according to UVV/VBG 103. 
Therefore take care on correct dose of cleaning 
agent and correct soaking time of exposure! 
We recommend the use of ultrasonic devices, clean-
ing devices, and equipment-care systems especially 
designed for the cleaning of handpieces and angular 
instruments. 
The proper cleaning of the instruments is highly im-
portant, in order to prevent debris from separating 
from the instruments under steam pressure during 
sterilization, and from clogging the filters, nozzles, 
and valves of the autoclave. Joints and hinges must 
be cleaned thoroughly with a brush. Rinse off all 
cleaning and disinfecting agents under running wa-
ter by using the brush before the instruments are 
loaded in the autoclave. These agents can other-
wise cause corrosion. Make a final rinse with dis-
tilled water and dry the instruments. 
Turbines and contra-angles must be oiled according 
to manufacturer's instructions to preserve their long 
life. 
New instruments 
The cleaning process as described above has to be 
undertaken with new instruments too because they 
often are covered with residues of oil, dirt or grease 
coming form the production. 
 
2.2  Formation of rust = foreign rust ____________________________________________  
It has already been said that the materials used for 
the autoclave prevent any formation of rust. 
The appearance of rust marks are caused by out-
side sources. It comes from instruments or other 
metal objects made of ordinary or stainless steel 
where the galvanic coating is damaged. In many 
cases, only one faulty instrument can contaminate 
many other and finally cause rust corrosion of the 
autoclave. With alloy cleaning materials, foreign rust 
has to be removed from instruments and from the 
basket in which they are loaded. Do not use any 
kind of steel wool or brushes. Dirt can be cleaned 
with a fluff-free damp cloth. The cloth can also be 
soaked with surgical spirit. 
2.3  Cleaning and care of the autoclave _________________________________________  
Autoclave vessel 
The vessel should be inspected at least once a 
week to check for dirt and deposits. Dirt should be 
wiped by using a soft fluff-free cloth soaked in alco-
hol. If stubborn spots are difficult to remove, we rec-
ommend the use of mild stainless steel cleaning 
product such as Sidol or an equivalent (with a pH 
range of 5...8). Be sure that no particles of dirt or 
other residue remain in the pressure vessel. 
Finally wipe the vessel with a damp cloth and run at 
least one empty sterilization process. 
Do not use paper towels, pot cleaners or brushes for 
cleaning the vessel. 
Sieve insert for the pressure vessel 
The pressure vessel (37) is provided at its bottom 
with a sieve insert which can be inserted and re-
moved. It prevents particles of dirt and debris from 
entering the lines which branch off from the bottom 
of the pressure vessel. This sieve should be re-
moved only if there is a great amount off coarse 
residue in the sieve. 
IMPORTANT
: Before removing the sieve to clean or 
replace it, the rest of the autoclave must be thor-
oughly cleaned. By no means should particles of 
debris be allowed to enter the openings located un-
der the sieve insert, use a suitable hook to reach 
down under its frame and lift it out. 





 
 
page 10 
Door gasket 
Check the door gasket every week for damage. If it 
is dirty, clean it with commercially available mild liq-
uid cleansers (with a pH between 5 and 8), or with 
methylated alcohol (C
2
H
6
O). Do not use cleansers 
which contain vinegar for complete cleaning. The 
gasket can be pulled out of the mounting groove and 
then later pressed back into place. 
Replace damaged gaskets immediately. 
Sliding door 
Pull out the door gasket. Spread out a non-ravelling 
(non-lint, non-fuzzy) cloth which has been soaked in 
methylated alcohol, onto the rectangular autoclave 
pressure vessel. Then carefully use gentle pressure 
to wipe off the sliding door on the cloth. After clean-
ing, press the door gasket back into its mounting 
groove. 
Outer-casing parts 
In order to clean the outer parts of the autoclave, 
also use mild cleansers or alcohol. 
2.4  Testing the function of the autoclave________________________________________  
Regular 
As an user of the autoclave, you are able to control 
the effectiveness of sterilization with the control in-
struments and the sterilizing time. A successful ster-
ilization is achieved if the pressure gauge indicator 
shows a value between 2 and 2.1 bar and the tem-
perature is within a range from 134°C to 135°C for at 
least 3½ minutes. For detailed information con-
cerning the control instruments, see chapter 5.2. 
The parameter-control system automatically moni-
tors these conditions at all times. If the monitored 
values exceed the established limits, a fault will be 
reported on the autoclave itself, and in the printout. 
Periodic (twice yearly) 
The German norm DIN 58 946, part 8, chapter 3.2 
recommends: 
"A periodic test is performed at place of installation 
in intervals of, for example 6 months. The test 
should confirm that the sterilizing apparatus sterili-
zes by following the manufacturer's instructions." 
German medical and hygienic institutes are sending 
spores in order to test the sterilizing apparatus. They 
evaluate the sample and confirm the solution on a 
form. 
DIN 58 946, Part 4, and the German Pharmacopoeia 
(DAB 10) stipulate that special test strips must be 
used to check steam autoclaves with spores of Ba-
cillus stearothermophilus (for example, the prod-
uct ATTC 7953, paper Spore Strips, made by the 
Oxoid company, Cd. no. BR 23). 
For MELAquick 12
® 
 (i.e., chamber volumes of 
1...3 dm³), DIN 58 946, Part 8 stipulates that three 
bio-indicators (plus a positive sample) must be used. 
A spore test can in any case be used to successfully 
verify the sterilisation effectiveness of the autoclave 
only in conjunction with the sterilization pro-
gram. 
Test spores which are already packed (for example, 
spore strips in paper packing, test tubes, or the 
product Attest) may not be again placed into the 
autoclave in a packed state. 
It is necessary to make the spore test under sterile 
conditions. This means, for example, that it is not 
possible after sterilization to put the spore sample in 
the same package in which it was sent to you, or to 
touch the sample with the same tweezers used be-
fore. Otherwise, recontamination will take place. We 
recommend sterilizing the tweezers with the sample. 
The positive sample which is not sterilized must be 
kept separate from the sterilized samples.  
IMPORTANT: 
If the spore sample is contained in an tube which is 
perforated only on one size (for example, the prod-
uct Attest made by company 3M), then follow the fol-
lowing instructions: 
Never place such tubes into the autoclave with the 
perforation upward (with the product Attest, the per-
foration is in the brown closure cap). 
Since our autoclave operates in accordance with the 
gravitation principle, in which the required air venting 
takes place downward, the perforation must face the 
bottom for best results. At the very least, the perfora-
tion must face toward the side, as is the case for in-
serted tubes. 
 
If you receive custom-made spore preparations 
which are directly sealed in paper / plastic pack-
ages, then make sure that the steam has unre-
stricted contact with all paper sides of the package. 
Here, it is also necessary that the paper side of the 
package face downward or to the side. 
 





 
User Manual 
MELAquick
®
12
 
page 11 
3 Installation 
3.1  Positioning the autoclave _________________________________________________  
Side gap 
The autoclave must have a distance of at least 
10 cm to a wall and 20 cm of free space above.  
Setting up 
For error-free function, the autoclave must be placed 
on a nearly horizontal surface. 
Installing the autoclave during winter period 
If the autoclave is very cold, it is necessary to wait 
with the sterilization/disinfection for some hours in 
order to make drying of condensation water in the 
inner parts possible. 
 
3.2  Connection of water discharge_____________________________________________  
The autoclave works with the one-way system. 
While processing, water vapour flows with pressure 
into the MELAG condensation container No. 120 
(23). The steam is condensed in the container via a 
cooling tube. 
Installation of the condensation container 
The container should be placed directly under the 
apparatus and enable easy access, but in every 
case in a lower position than the autoclave. The 
hose can be lead to the autoclave through a hole in 
a table with 7 mm in diameter and should have the 
shortest length, but not more than 1.5 m. A higher 
length does not spoil the function or effectiveness of 
the autoclave. The effect of a longer hose is that the 
lamp which indicates the "End" of a process, lights 
(in combination with a beep) although the pressure 
in the vessel has not been completely reduced. The 
sliding door can only be opened if the pressure is 
0 bar. This is indicated on the pressure gauge (6). 
Connecting the condenser container 
The Teflon hose you have obtained with the delivery 
of the MELAquick12
® 
 has to be shortened to the 
correct length so that a constant fall is achieved. 
Use a sharp knife. If the hose is too long it may oc-
cur a "sack" of water that leads waste water back to 
the apparatus. 
Please put the hose in a position where it cannot 
be touched unintentionally because the hot hose 
may cause injuries. 
To connect the condenser container, insert the pres-
sure-safe Teflon hose into the connector (18) at the 
back of the autoclave as far as possible. Therefore 
you have to overcome a first resistance to get to the 
end of the connector. The other end of the hose is 
already attached to the lid of the condenser con-
tainer (23). 
Make sure that the hose is fully inserted, otherwise 
this will lead to an escape of steam. 
Filling the condenser to the MIN-mark 
To prevent the formation of bacteria in the con-
denser, the container should be filled with approxi-
mately 150 ml of  normal disinfection liquid and then 
filled up with tap water to the MIN-mark.  
This procedure has to be fulfilled at the first time of 
installation and after each time the container was 
emptied. 
Emptying the condenser container 
The condenser (23) should be placed for easy ac-
cess in order to check the water level in the con-
tainer. If the water reaches the MAX-mark, the con-
tainer must be emptied immediately. 
We recommend to empty the condenser container 
each time purified water is added to the reservoir in 
the autoclave. Thus you ensure a regular working 
procedure without an overflow of the condenser con-
tainer. 
Never operate the autoclave without connecting 
the required condensate tank. 
 
IMPORTANT: Never empty the condensate tank 
while the autoclave is in operation, owing to the 
danger of burning the operating personal. 
DANGER OF SCALDING! 
 





 
 
page 12 
3.3  Filling the water reservoir _________________________________________________    
When turning on the autoclave for the first time 
(where the reservoir is empty) or when the reservoir 
is not filled with enough water, the light "WATER" 
lights on. On lack of water the autoclave will not 
work. 
For the first filling or refilling of the reservoir the 
black lid (3) at the back of the apparatus must be 
removed and the reservoir underneath has to be 
filled up with distilled water until the lower corner of 
the trapeziform filling nozzle is reached. This is done 
while the sliding door of the autoclave is closed. Use 
a funnel if you want to fill from a large water con-
tainer. 
Total capacity of tank:    4.50 l 
Re-filling with water:  approx. 4.25 l 
Attention: 
• Make sure that the water quality is adequate, in 
accordance with chapter 5.3. 
• do not move or tilt the autoclave when filled with 
water. 
• Drain water before transport or if the autoclave is 
not used for more than 14 days (see Sec-
tion 5.3.2.). 
3.4  Connection of the logging printer __________________________________________    
The MELAquick12
® 
 autoclave is equipped on the 
equipment side with a serial printer interface (21). 
When the MELAprint40
®
 dot matrix printer (order no. 
298) is connected, a log is printed out for every cycle 
program. 
The interfacing cables included in the normal order 
for the printer are for power supply and data trans-
mission, they must be connected between the 
printer and the jacks 20 and 21 on the rear side of 
the 
autoclave. When connecting the 24-pole plug of the 
cable (to the printer) and the 9-pole plug of the cable 
(to the autoclave)use also the attached screws. 
When installing the printer, it is also necessary to 
load the paper in accordance with the instructions 
supplied with the printer. 
When the power switch on the autoclave has been 
switched on, and when paper has been loaded into 
the printer, the operating-voltage signal lamp 
„
P“ and 
the status indication ON/OFF Line 
„
SEL“ will glow. 
3.5  Setting the time of day and the date_________________________________________    
The internal clock of the autoclave has been cor-
rectly set before it leaves the factory. It continues to 
run, powered by its battery, even when the auto-
clave is switched off. The installed battery has a ser-
vice life of 7...10 years.  
It is necessary to set time and date only if a printer is 
in use, because it will appear only on the printout.  
If it becomes necessary to set the internal clock (for 
example, for a change between winter and summer 
time), then proceed as follows: 
•  First hold the 
„
SELECT“ button (15) pressed, and 
then briefly press the button 
„
START“ (7). Then 
release both buttons. The device is now in the 
SET mode, and 
„
Set time and date“ is output on 
the printer, followed by a table with the current 
settings for time and date. 
• The 
„
WATER“ lamp (8) will also flash slowly, and 
the current value for 
„
hours“ will be printed out by 
the printer. 
•  By pressing the 
„
SELECT“ button (15), it is then 
possible to switch consecutively forward through-
out the following sequence: 
- To 
„
minutes“ -- the lamp for 
„
DOOR“ (9) will 
then flash 
- Then to 
„
seconds“ -- the lamp for 
„
FAULT“ (10) 
will flash 
- Then to 
„
day“ -- the 
„
READY“ lamp (11) will 
flash 
- Then to 
„
month“ -- the lamp 
„
RUNNING“ (12) 
will flash, and then finally 
- To 
„
year“ -- the lamp 
„
END“ (13) will flash 
  After each switching operation, the printer will 
output the current setting. 
• Use the button 
„
START“ (7) to change each of 
the values selected. You can briefly press the 
„
START“ button (7) several times in a row, which 
will increase the current setting by 1 unit for each 
pressing. Or, you can hold down the 
„
START“ 
button (7) longer, which will cause a rapid in-
crease in settings. You will hear a short beep 
every time the setting increases by one incre-
ment. When the 
„
START“ button (7) is not 
pressed for more then 2 seconds, the current set-
ting will be output by the printer. 
• If the 
„
SELECT“ button (15) is pressed again af-
ter the setting opportunity for the 
„
year“, the date 
and time of day will printed out again in tabular 
form, and the device will leave the SET mode. 
3.6  Empty sterilization process________________________________________________  
When the MELAquick12
® 
is put into operation for the 
first time, it is absolutely necessary to run two con-
secutive sterilization cycles with no instruments in 
the autoclave. This is necessary to remove the air 
from tubing system of the autoclave, as well as any 
antifreeze agent which may have been installed in 
the factory, and which must be removed from the 
waterfeed system. During this first (empty) sterili-
zation cycle, it is normal that the autoclave will 
switch to fault no. 4 (see Section 8) to indicate a 
lack of water. Should this situation arise, switch off 
the autoclave for at least 10 seconds, then switch on 
and start a cycle again. 
 





 
User Manual 
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®
12
 
page 13 
3.7 VDE-requirements _______________________________________________________  
Due to the valid VDE-requirements, this autoclave is 
not suitable in areas with danger of explosion. 
It may be repaired only by the manufacturer or a li-
censed service unit. 
Electrically powered devices of this nature 
should not be operated unless they are under 
constant supervision. 
3.8 Safety precautions _______________________________________________________  
1. Never use the autoclave without the connected waste water hose (22) and the condenser con-
tainer.  
DANGER OF SCALDING! 
2.  The hose must be fully inserted into the hose coupling at the back of the autoclave. It also has to 
be kept straight and with a drop to the condenser container! 
3.  During use the hose and the condenser container get hot. DO NOT TOUCH! 
4.  Empty the condenser container (23)each time the water reservoir is refilled! 
5.  When opening the sliding door (1), keep your arm to the side. Small quantities of remaining steam 
could rise out of the opened door! 
6.  When the sliding door is open, do not touch the exposed hot metal parts. DANGER OF BURNING! 
To take out the basket/instrument carrier, always use the handle provided! 
7.  Empty water reservoir (3) before transport! 
8.  Do not tilt the autoclave when filled with water! 
9.  Do not use the LOCKING HANDLE (2) to lift or transport the autoclave. 
10. Do not open the enclosure of the autoclave. The components on the inside of the device can be 
serviced only by a trained specialist. 
  WARNING: It is necessary to remove the power plug of the autoclave from mains power socket in 
order to diconnect the device from all poles of the AC power supply. 
 
 
 
 





 
 
page 14 
4  For every sterilization / disinfection cycle 
4.1  Main switch, pre-heating of the vessel_______________________________________  
At the beginning of one working day, press the main 
switch to turn on the autoclave and select the pro-
gram if necessary. The autoclave's chamber will 
automatically pre-heat. During this heating period 
(about 10...15 min. for sterilzation, and less than 10 
min. for disinfection), the lamp 
„
READY“ (11) will 
flash. When the pre-heat temperature is reached, 
the blinking sign changes to a continuous light. Now 
the specified program can be started. 
Once the pre-heat process has been finished, the 
pre-heat temperature will be kept on a constant level 
so that the autoclave can be used without in-
terruption until it is turned off. 
It is recommended to keep the sliding door closed 
during the pre-heat period. Thus the autoclave can 
be used earlier due to less heat loss. 
At the end of a working day, the main switch should 
be pressed to turn the autoclave off. 
4.2  Selection of program _____________________________________________________  
The 
„
SELECT“ button (15) on the control panel of 
the autoclave is used to choose the desired pro-
gram. The program selected is then signalled on the 
corresponding signal lamps (16, 17). 
Before leaving the factory, the autoclave is set to 
sterilization. 
Each time that the autoclave is switched on by the 
power switch 
„
MAIN“ (4), the program selection is 
the same as that selected when the device was 
switched off. 
The operator should select the desired program 
as soon as possible after switching on the elec-
trical power. If the autoclave has been already 
preheated  (the 
„
READY“ lamp (11) glows), and if 
the program is only then switched from 
„
Disin-
fection“ to 
„
Sterilization“,  the autoclave will run 
through a brief reheating phase of about 5 minutes. 
If the program is switched from 
„
Sterilization“ to 
„
Dis-
infection“ after preheating, then the autoclave will 
run through a cool-down  phase for the pressure 
vessel, of up to 45 minutes (see Section 4.1). During 
this reheating or cool-down phase, the 
„
READY“ 
(11) lamp will flash, and the autoclave cannot be put 
into operation. 
IMPORTANT: 
• Items for sterilization can also be sealed into 
transparent sterilzation packages. 
• Steam pressure disinfection is permissible only for 
instruments which are unpacked. 
• This autoclave cannot disinfect or sterilze liquids 
or textiles. 
• Observe the instructions above on the reheating 
and cool-down phase if the program is changed 
between sterilization and disinfection after the 
autoclave has been preheated.  
4.3  Items to be sterilized _____________________________________________________  
Carrier basket, instrument carrier 
Never use the autoclave without one of the specifi-
cally provided carriers. Otherwise a malfunction may 
occur due to lack of ventilation or blockage of a 
steam tube. For universal use of your ME-
LAquick12
®
, you have 3 possibilities: 
• For general purposes use the insert basket (part 
No. 121). It provides a sterilization of 12 turbines 
and contra-angles. Other instruments with a maxi-
mum length of 16cm can be sterilized in this bas-
ket, too. If you want to sterilize instruments with 
very small size, e.g. endodonic instruments, the 
basket has a half-rounded container which can be 
hung either in a higher or lower position. 
• The  instrument carrier (part No. 122) is fitted 
with 7 ISO adapters that can be used with instru-
ments with ISO connectors. These instruments 
can easily be sterilized in the MELAquick12
® 
. 
• The instrument carrier (part No. 123) is fitted 
with 7 round holders which can be used with in-
struments whose manufacturers recommend a 
sterilization with the instrument's head pointing 
down. 
Sterilization packages 
The items to be sterilized can be sealed in a trans-
parent sterilization package like MELAfol 
®
 (one side 
paper, one side film). For sealed items only use the 
basket, order no. 121. It is important that you do not 
place too many instruments in the basket. They 
must be placed in a position where the incoming 
steam can reach all paper sides of the sterilization 
packages. When sealing the objects inside the ster-
ilization packages, make sure that the sealing seam 
has a width of at least 8 mm in accordance with 
DIN 58953, part. 7. The MELAG package sealing 
device MELAseal 
®
 seals such plastic bags with a 
sealing seam of 10 mm. 
Temperature sensitive items 
Especially plastic articles and turbines or instru-
ments with fibre optics are very sensitive to high 
temperature. So look for the maximum temperature 
to which the instruments can be exposed, according 
to the manufacturer's recommendations. Please re-
fer to their specific instructions. The regulation with 
microprocessors in combination with highly sensitive 
sensors ensure that the temperature in the chamber 
and its wall never exceeds the maximum tempera-
ture of 135°C for sterilization and 107°C for disin-
fection. 
Liquids and textiles 
The autoclave is not suitable for sterilization of liq-
uids or textiles! 
 





 
User Manual 
MELAquick
®
12
 
page 15 
4.4  Preparation of instruments ________________________________________________  
The instruments have to be cleaned and cared for 
very thoroughly as described in chapter 2.1. In addi-
tion, clean and oil hand pieces according to the 
manufacturer's instructions. 
4.5 Loading ________________________________________________________________  
The closed and locked sliding door (1) is opened by 
turning the knob (2) for 90° counter clockwise. 
Shortly before the end of this quarter-turn, the turn-
ing becomes slightly more difficult while the sliding 
door is raised. When 90° turn is complete, the mark-
ing on the knob will then point along the axis of the 
autoclave. To open the door, push it toward the rear 
by using the knob. Do not press down with the 
knob: this would apply pressure to the door gasket 
and would cause the door gasket to jam. 
Put the loaded basket (No. 121) or instrument car-
rier (No. 122/123) into the sterilization chamber by 
using the supplied handle. 
 
Never sterilize instruments without using a bas-
ket or carrier. 
Now pull the sliding door forward, again by taking 
the knob without pressing down, until the end is 
reached. For locking the door, turn the knob with 90° 
clockwise. 
The red lamp "Door" (8) must go out. 
If you move the knob with pressure, it may happen 
that the door's seal will be shifted or even damaged 
which causes a malfunction of the autoclave (see 
also chapter 7.7 and 8.2.6). 
4.6  Starting the sterilization / disinfection_______________________________________  
To start the desired program, press the start button 
(7). This is followed by a short beep which confirms 
your request. 
During the following 2 seconds, the autoclave auto-
matically tests the quality of the distilled or deminer-
alized water in the tank. If the water quality is not 
adequate, a warning signal will follow, or in the worst 
case a malfunction will be registered. In both cases, 
the lamp 
„
WATER“ (9) will flash. See Section 1.7. 
Water will then be automatically pumped into the 
steam generator (for 16 seconds); this function is 
clearly audible. 
At the same time, the steam generator starts and the 
air in the chamber is pushed out through a current 
jet. 
Pressure and temperature are built up under control 
of microprocessors. A blinking sign of the lamp 
'"RUNNING" (12) indicates the momentary heat-
ing-up phase. 
When the required pressure (2 bar) and temperature 
(134°C) for sterilization (0.2 bar and 105°C for disin-
fection) is reached, the lamp "RUNNING" shows a 
continuous light which announces that the actual 
sterilization time is now in action. 
During the whole process, first air and, after a while, 
steam flows via a pressure safe hose from the ves-
sel to the condenser container. 
Attention: hose is getting hot! 
Remember that the running program can only be 
stopped by pressing the main switch or by trying to 
open the sliding door. In the last case, a fault reac-
tion will be triggered (lamp "FAULT" (10) lights) 
which automatically reduces the pressure. The door 
can only be unlocked and opened if the pressure 
has fallen down to 0 bar (see gauge (5)). 
Conditions for ability to start: 
The process cannot be commenced, if: 
•  there is lack of water 
•  the sliding door is not closed and locked 
•  the pre-heat process has not finished yet and the 
lamp "READY" does not light without interruption 
•  the quality of the distilled or demineralized water 
is not adequate. 
•  there is a fault 
•  a program is in progress 
If in any cases above the start button is pressed, you 
will hear a beep for 2 seconds as a mistake in oper-
ating. 
 
4.7  Automatic pressure release _______________________________________________  
At the end of a sterilization process, the autoclave 
will automatically let the steam out. Then the lamp 
"RUNNING" goes out an the lamp "END" (13) 
comes on. The end of each process is confirmed by 
4 short and 1 long beep. 
 
 





 
 
page 16 
4.8  Automatic printout of the log ______________________________________________  
After the lamp 
„
END“ (13) glows, and the acoustic 
signal sounds five times, the log will be printed out 
automatically if the printer has been connected and 
is ready for operation. See Section 1.5. 
4.9  Successful end of a process_______________________________________________  
The acoustic signal and the light of lamp "END" 
indicate the completion of a successful steriliza-
tion/disinfection process. 
This result says that the autoclave's vessel was suf-
ficiently ventilated and the minimum values for pres-
sure and temperature were definitely fulfilled during 
the whole process. This is also documented in the 
log if the printer has been connected. 
However, if the autoclave indicates a fault, the mini-
mum values were not achieved, even if you open the 
door and the lamp "FAULT" does not shine any 
more.  In this case, you cannot assume a suc-
cessful process. The instruments have to be re-
garded as unsterile. 
The required log will also be printed out in this case. 
See Section 1.5. 
4.10  Removal of instruments __________________________________________________  
When the pressure is 0 bar and the lamp "END" 
lights, the vessel can be opened. To unlock the 
sliding door turn the knob 90° anti-clockwise. Shortly 
before the end of the turn, you have to overcome a 
slight resistance before the door is completely 
unlocked. 
 
             
You can see the lamp "END" (13) go out while lamp 
"READY" (11) is lighting again. The autoclave is now 
ready for a new start. 
If the sliding door cannot be completely unlocked, 
there is still pressure in the vessel which is produced 
by post-vaporization. Then the pressure operated 
safety lock is still in operation. In this case, lock the 
door once again and wait for a few seconds until the 
pressure on the gauge (5) has fallen to 0 bar. Now 
unlock the door and pull the knob (2) without 
pressing it down. 
4.11 Drying _________________________________________________________________  
After sterilization, unsealed sterilization items are 
dry and can be taken out immediately. 
Sealed items or items to be disinfected should be 
left in the hot vessel for a few minutes with the slid-
ing door open. This is recommended for complete 
drying. 
4.12  Particuliarities of the disinfection___________________________________________  
Packing 
Items must not be wrapped. 
Selection of the program 
The operator must use the 
„
SELECT“ button (15) on 
the control panel to switch from sterilization to the 
disinfection program. Then the signal lamp for 
„
ster-
ilization“ (16) will go out, and the lamp for 
„
disinfec-
tion“ (17) will glow. 
Cool-down phase 
If the autoclave is set to the sterilization program, if it 
is fully heated up, and if it is then switched to the dis-
infection program, the 
„
READY“ (11) lamp will flash 
up to 45 minutes, until the autoclave cools down to 
the preheating temperature for disinfection. Also see 
section 1.3. During this period, it is not possible to 
start the disinfection program. 
4.13 Overheat protection ______________________________________________________  
Overheat excluded 
Overheat during error-free process is generally ex-
cluded due to the concept of separate steam gen-
eration in combination with electronic-parametric 
regulation. The limit of 135°C (107°C) cannot be ex-
ceeded. 
Steam temperature control 
Additionally, the temperature of steam is electroni-
cally controlled. If the limit temperature of 140°C 
(112°C) is exceeded owing to a defect, the running 
program will also be interrupted, and the 
„
FAULT“ 
lamp (10) will glow. 
Temperature limitation 
To avoid (e.g. complete failure of electronic / heater 
cut-out) possible overheats and thus endangering 
the items to be sterilized even under unusual condi-
tions, the autoclave has two separate temperature 
limitors, one for the vessel and one for the steam 
generator. These two work independently from the 
safety system described above and will directly cut 
CORRECT  INCORRECT





 
User Manual 
MELAquick
®
12
 
page 17 
power if temperature exceeds the limit. If the tem-
perature monitor system triggers, the respective 
heating system will be switched off, and the water 
pump will simulanteously start to cool the steam 
generator. If the electronic system is functional, the 
lamp 
„
FAULT“ (10) will also glow, indicating a fault. 
Interruption of the sterilization 
The light of lamp "FAULT" shows in every case that 
the sterilization/disinfection program was not fully 
completed. The items have to be considered as un-
sterile. 
When the fault light blinks (time is beyond limit) and 
goes out if the door is opened, the sterilizing cond-
itions were not achieved fast enough or did not re-
main long enough. The autoclave returns to ready 
state after having opened the door. After having 
checked the apparatus and removed the cause of 
fault (too much load / ventilation holes blocked by 
load / sliding door not tight because of improper 
closing), you are able to continue your work imme-
diately with the autoclave. 
If the fault message cannot be removed by opening 
the sliding door, you either have tried to open the 
door during the process or there is a defect in the 
apparatus (heating elements / temperature sensors). 
After switching off the main switch briefly (at least 
10 seconds), the autoclave should be ready again. 
For repeated fault messages, the cause of failure 
must be found and removed by a service technician; 
also pay attention to chapter 8. 
 
4.14  Process control _________________________________________________________  
The autoclave offers the following possibilities for 
controlling a safe sterilization/disinfection process: 
Successful conclusion of a process 
As soon as a sterilization/disinfection is completed 
successfully, i.e. keeping the required parameters 
for pressure and temperature in the prescribed time, 
the lamp 
„
END“ lights and an acoustic signal can be 
heard. If the log printer is connected, the successful 
end of the cycle will be documented on the printout. 
Pressure-temperature correlation 
During process, the correlation of temperature with 
pressure can be controlled by observing the ther-
mometer (6) and the pressure gauge (5), according 
to the curve for saturated steam (e.g. 2-2.1 bar with 
134-135°C). The precision of the indicator instru-
ments must be taken into account here: see Section 
5.2. 
Electronic monitoring of parameters 
During running of the program, the following pa-
rameters will be automatically monitored under mi-
croprocessor control: 
Heat-up time
 
The maximum heat-up time is normally 3 minutes. 
If overloading, insufficient venting, or fault in opera-
tion prevent the autoclave from achieving the values 
required by the selected program for pressure and 
temperature within 5 min., then the program will in-
terrupt owing to time overrun, and the lamps for 
„
FAULT“ (10) and 
„
RUNNING“ (12) will flash. 
Sterilization/disinfection time
 
During sterilization/disinfection process, the pa-
rameters pressure and temperature are constantly 
controlled. The sterilization/disinfection time of 
4 / 6 minutes will only run if both parameters reach 
the required values (lamp "RUNNING" lights). If the 
autoclave exceeds the control time of 5.5 minutes 
for  sterilization / 7.5 minutes  for  disinfection  due  to 
faulty run, the program will also be stopped because 
of exceeding time. The lamps for 
„
FAULT“ (10) and 
„
RUNNING“ (12) will flash in this case. 
Exceeding steam temperature
 
If the autoclave exceeds the steam temperature of 
140°C during sterilization or 112°C during disinfec-
tion due to a fault, the program will also interrupt in 
such case, and the lamp for 
„
FAULT“ (10) will glow. 
The lamps for 
„
READY“ (11) and 
„
RUNNING“ (12) 
will flash. 
Temperature limitation 
The automatic temperature limitation has already 
been described (See Section 4.13). 
4.15  Sterilizing frequency _____________________________________________________  
Because of its parameters control system and its op-
timised heating, the MELAG-autoclave 
MELAquick12
® 
 can be used for steriliza-
tion / disinfection without interruption. So 8-
10 sterilizations per hour are possible. 
 
5  Further informations about sterilization 
5.1  Total operating time______________________________________________________  
Operating time 
"The operating time is the time needed for steriliza-
tion without taking account of loading and emptying." 
(DIN 58900) 
Due to the parameter regulation of the autoclave, 
the operating time is optimised mainly depending on 
the number of items to be sterilized and the tem-
perature of the apparatus. The minimum operating 
time (small load, immediate sterilization before) 
needed for sterilization is about 5.5 minutes and 
about 7.5 minutes for disinfection. The maximum 
time (maximum load, first process after complete 
pre-heat) is about 8 minutes for sterilization and 
9 minutes for disinfection. 
Included times 
The operating time includes times for pressure gen-
eration, ventilation and heat-up of instruments and 
vessel as well as for sterilization which consists of 





 
 
page 18 
equalization time, killing time and an extra charge for  safety. 
 





 
User Manual 
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®
12
 
page 19 
 
5.2  Accuracy of process regulation ____________________________________________  
 
The analogue instruments for pressure and tem-
perature of the MELAquick12
® 
 work completely in-
dependently from the microprocessor regulation and 
are only for additional information about the run 
state of the autoclave. 
Because of their small size, the accuracy of these 
instruments is only ± 0,1 bar (pressure gauge) and  
± 2°C (thermometer). 
Owing to the time delay of the temperature sensor, it 
can happen that the indication of the temperature 
reaches the correct value only after beginning of the 
sterilization or disinfection time: i.e., while the lamp 
„
RUNNING“ (12) is glowing, and after the required 
temperature has already been reaches in the 
pressure vessel. 
It may also happen during continuous operation, as 
a result of constant high temperature of the auto-
clave, that the temperature indicates on the ther-
mometer is 2°C higher than the temperature shown 
for the first sterilization or disinfection cycle. In the 
actual sterilization compartment, however, there will 
be no temperature deviation. 
Microprocessor control 
The electronic control system, on the other hand, 
operates with an absolute precision of 0.5°C and 
controls the sterilization or disinfection temperature 
with a maximum deviation of ± 0.3°C. 
The microprocessor regulation in combination with 
separate steam generation excludes an overheat of  
instruments and of the vessel, too. 
 
5.3  Use of aqua dest / aqua dem_______________________________________________  
Quality requirements 
It is important to use distilled water (aqua dest) or 
demineralized water (aqua dem) for steam steriliza-
tion. 
As directions for water quality, refer to the values in 
the nearby table according to CEN-standard DIN EN 
13060. 
For the operation of the MELAquick12
® 
 and for all 
other MELAG autoclaves, however, battery water 
in accordance with VDE 0510 is also adequate. 
The stipulations of VDE must be strictly observed 
here, however: conductivity upon processing of the 
water ≤ 10 µS/cm*
)
, and upon use ≤ 30 µS/cm*
)
, pH 
identical to stipulations of DIN EN 13060, and resi-
due of evaporation comparable. 
Automatic testing of conductivity 
Immediately after start of he program, the autoclave 
tests the water conductivity in the water storage tank 
(see Section 1.7). 
If the water quality is adequate, the program will run 
normally. If the water conductivity is between 
approx. 25 and 40 µS/cm*
)
 , the lamp 
„
WATER“ (9) 
will  flash to warn the operator. The program will, 
however, continue to run normally. If the water con-
ductivity is greater than approx. 40 µS/cm*
)
 , the 
lamp 
„
WATER“ (9) will flash, a fault message will 
be triggered, and the lamp 
„
FAULT“ (10) will glow. 
In such case, in order to protect the instruments and 
the autoclave, the program will not start. The opera-
tor must replace the water in the tank by better (for 
example demineralized) water and press the 
„
START“ button (7) again. 
Suppliers of adequate water  
Battery water in accordance with VDE 0510 is eco-
nomically supplied by all major drug stores, super-
markets, home-construction marts, as well as from 
wholesalers. In Germany, however, the seal for 
VDE 0510 must be expressly displayed on the label. 
Functional effectiveness 
If you do not pay attention to the directions above, 
deposits of lime in steam pipes, valves and current 
jet can impair the autoclave's functional effective-
ness. Aggressive water (pH <5 or >7) can also dam-
age the apparatus. 
It is only for high values of conductivity that the 
autoclave triggers a warning or fault alarm. See Sec-
tion 1.7. 
Steam formation 
The extent of stain formation on instruments de-
pends on the quality of water used for steam gen-
eration. 
 
vapour residues 
≤ 
10 mg/l 
silica, SiO
2
 
≤ 
1 mg/l 
iron 
≤ 
0,2 mg/l 
cadmium 
≤ 
0,005 mg/l 
lead 
≤ 
0,05 mg/l 
heavy metals expect the 
ones above 
≤ 
0,1 mg/l 
chlorides 
≤ 
2 mg/l 
phosphates 
≤ 
0,5 mg/l 
conductivity 
≤ 
15 
µS/cm*
)
 
pH - value  5 to 7 
colour colourless, clear 
without residues 
hardness 
≤ 
0,02 mmol/l 
 
*
)
  µS/cm = Micro Siemens per centimetre
 





 
 
page 20 
5.3.1  Amount of consumption _________________________________________________________   
Water in the reservoir decreases each process with 
the amount needed for one sterilization/disinfection 
(one-way system).  
The MELAquick12
® 
 requires approx. 150 ml of dis-
tilled or demineralized water per sterilization or disin-
fection cycle. 
When the water reservoir is full, it is possible to 
conduct approx. 28 sterilization cycles until the lamp 
„
WATER“ (9) glows. Then the operator must refill the 
water tank. 
5.3.2  Emptying the reservoir___________________________________________________________ 
If the autoclave must be transported, or if it will re-
main out of operation for a lengthy period of time 
(over about 14 days, depending on the water quality 
and temperature), then it is necessary to empty the 
water storage tank to prevent soiling due to growth 
of algae, etc. 
For emptying the water storage tank, it is necessary 
to turn the autoclave so that the rear part protrudes 
about 12...15 cm over the edge of the table. You can 
now see a rubber bung (19) under the autoclave. 
Pull out the bung and the hose to which the bung is 
connected until you can feel a definite resistance. 
Then put a container underneath, pull the bung out 
of the hose and wait until the reservoir is completely 
empty. Stick the bung back into the hose and the 
hose back into the autoclave. 
5.3.3  Refilling / Replacement __________________________________________________________ 
Lamp 
„
WATER“, indicating lack of water 
The light of lamp "WATER" shows that the amount 
of water in the reservoir is not sufficient any more. 
With this lamp on, there is no possibility to start a 
program. The reservoir has to be refilled with aqua 
dest/aqua dem until the lamp goes out. The maxi-
mum level is reached with the lower edge of the tra-
pezi-form filling nozzle. 
If lamp "WATER" comes on after a start of a process 
and during pumping, it has no influence on running 
the program. 
The remaining amount of water in the water storage 
tank is in any case sufficient for the started sterilisa-
tion or disinfection cycle to run to completion. 
Replacement in case of pollution 
If dirt has come into the water reservoir because of 
misoperation, the reservoir has to be rinsed and 
cleaned, e.g. with a bottle brush. In every case, let 
off the water as described above and refill the reser-
voir. 
 





 
User Manual 
MELAquick
®
12
 
page 21 
6  Putting out of operation / Transport 
•  Switch off main switch. 
•  Pull out main plug, let autoclave cool down. 
•  Remove hose to condenser container from auto-
clave by pressing hard against the black ring of 
the connector (16) and pulling the hose out of 
the connector at the same time. 
•  Empty water reservoir as described in chapter 
5.3.2. 
• If possible, use the original packing to trans-
port the autoclave. Be sure in any case to addi-
tionally seal the autoclave inside plastic wrap-
ping, in order to prevent packing material from 
entering the water storage tank, etc. 
6.1  Transport under danger of frost ____________________________________________  
If freezing temperatures are possible during trans-
port, any water which may remain in the feed-water 
system must be removed in order to prevent dam-
age to the pump and the water lines. A service tech-
nician is required for this work, which includes the 
following steps: 
•  The autoclave must be switched on and pre-
heated. 
•  Empty the water storage tank as described in 
Section 5.3.2. 
•  Remove the metal side-enclosure panels from 
the autoclave. 
•  At the bottom left on the electronic circuit board 
there are four wire-clasp buttons / switches (22). 
The second from the bottom is the Test Button, 
which sets all outputs of the control system. 
Press this Test Button for the electronic control 
system until no more water is pumped on the 
output side of the water pump (through the thin, 
transparent hose). 
•  Open and close the sliding door several times 
until all the water remaining in the steam gen-
erator is expelled. This action will heat the air 
contained in the preheated pressure vessel, 
which will cause the air to expand and expel any 
water remaining into the condensor container. 
•  Switch off the power switch and unplug the 
power cable. 
•  Replace the metal side-enclosure panels on the 
autoclave. 
•  Disconnect hose to condenser container from 
the autoclave by pressing hard against the black 
ring of the autoclave's connector; at the same 
time pull the hose. 
•  Let the autoclave cool down. 
 
 





 
 
page 22 
7  Breakdowns without warning light 
The following instructions for breakdowns are pro-
vided to help the user resolve minor trouble himself, 
or to allow him a more accurate description of mal-
functions to his authorized dealer, warehouse agent, 
or customer-service representative.  
Bigger faults or damages are repaired only by 
appointed service engineers or by the manu-
facturer. 
7.1  No Indication or false indication of the operating state_________________________  
After having switched on the main switch (4), the 
autoclave shows its state of process by the following 
indicators: 
Door closed and locked: 
Lamp "MAIN" lights, 
Lamp "READY" blinks (if apparatus is still cold), 
Lamp "READY" lights (if apparatus is pre-heated), 
Lamp "WATER" lights (if there is lack of water). 
Door unlocked: 
Lamp "MAIN" lights, 
Lamp "DOOR" lights, 
Lamp "READY" blinks (if apparatus is still cold), 
Lamp "READY" lights (if apparatus is pre-heated), 
Lamp "WATER" lights (if there is lack of water). 
 
If no indication of any light: 
Is the autoclave plugged in? 
Is there current in the socket? When switching the 
main switch of the autoclave, lamp 
„
MAIN“ must 
come on.  
If power is available to the autoclave, and if the 
„
MAIN“ power switch (4) is switched on, but if no sig-
nal is provided, then it is possible that the main fuse 
in the autoclave is defective. 
You must notify the MELAG Customer Service De-
partment. 
In case of different indication: 
Switch off main switch and switch it on again after 
10 seconds. 
If -- despite attempting the measures described 
above -- the autoclave is still not in proper opera-
tional status, as would be indicated by the proper 
lamp signals given above, there is probably an elec-
trical defect within the autoclave. You must notify the 
MELAG Customer Service Department. If the elec-
tronic circuit board becomes dirty -- for example, if 
disinfecting agent enters the device through the for-
ward vent slots -- then it may be cleaned with methy-
lated alcohol (C
2
H
6
O). 
7.2  Lamp 
„
READY“ does not light continuously__________________________________  
If lamp "READY" blinks more than 20 minutes after 
having turned on the main switch, and the auto-
clave's vessel is still hot, you have previously 
changed from sterilization to disinfection program so 
that the autoclave is still cooling down to pre-heat 
temperature for disinfection (see 1.3). This can take 
up to 45 minutes. 
If the 
„
READY“ lamp (11) flashes more than 
20 minutes while the pressure vessel is cold  and 
no fault has been signalled, the temperature sensor 
of the preheating system is defective. You must no-
tify the MELAG Customer Service Department. 
7.3  Impossible to start a program______________________________________________  
Preheat phase / cool-down phase 
During the following phases, it is not possible to start 
a program: 
• During the approx. 10...15-min. preheating 
phase (only once, after first switching on the 
autoclave) 
• During the 5-minute reheating phase when 
switching from the disinfection to the sterilization 
program 
• During the cool-down phase  when switching 
from the sterilzation to the disinfection program. 
During one of these phases, the lamp 
„
READY“ will 
glow. The operator must wait until the end of the 
preheat, reheating or cool-down phase. 
Door contact  
A program start is only possible with the sliding door 
closed and locked. Lamp "DOOR" will go out when 
the sliding door is in closed position and completely 
locked. 
Check that door has been pushed to the end. 
If the lamp 
„
DOOR“ (8) does not go out through the 
door has been correctly locked by a quarter turn, 
then the contact has not been correctly set, or it has 
been damaged by violent sliding of the door in its 
locked position (the pushing rod has been bent in 
the door guide). 
You must notify the MELAG Service Department
 
The contact must probably be adjusted by removing 
the nut of the microswitch and readjusting the con-
tact position inside the apparatus (while the auto-
clave is hot). 
If the door contact rod is bent, the microswitch must 
first be removed, and then the contact rod must be 
straightened. Then the microswitch must be installed 
again (with the round side upward), and the door 
contact must be adjusted again (see above). 
Lack of water 
If lamp "WATER" lights, there is not enough water in 
the reservoir so that it is not possible to start a pro-
gram. 
Water reservoir has to be filled (see chapter 3.3). 
If the lamp does not go out when the reservoir is 
filled to the lower edge of its trapezi-form inlet, a ser-
vice engineer must check the water level switch of 
the container. 
It may be possible to trigger the switching process 
for the water-level indicator switch by tapping lightly 
against the autoclave or against the water storage 





 
User Manual 
MELAquick
®
12
 
page 23 
tank. 
Program still running 
When a process is running (lamp "RUNNING" lights 
or blinks) or the sliding door has not been opened 
yet after a completed process (lamp "END" is still 
on), it is not possible to start a new process. Wait 
until the process is over and open the sliding door. 
Note: 
If the "START"-button is operated in one of the 
above cases, you will hear a beep for 2 seconds be-
cause of misoperation. 
Faulty operation 
If lamp "FAULT" lights, it is not possible to start a 
program. 
7.4  The water pump does not start when the program begins ______________________  
It can happen that the water pump (47) starts with a 
delay: i.e., only within 30...60 seconds after pressing 
the 
„
START“ button (7), and not within two seconds 
as normal. Under such conditions, the program may, 
however, run normally through to the end, with the 
lamp 
„
END“ (13) signalling the proper end of cycle. 
In such case, it may be assumed that the steriliza-
tion or disinfection program has successfully run 
through to the end, but that the fuse for the pump 
output is defective. 
You must notify the MELAG Customer Service De-
partment. 
In such case, the pump (47) has not been properly 
activated by it’s output in the electronics system, but 
instead via the steam-generator output after trigger-
ing of the overheating protection system for the 
steam generator (33). The fuse for the pump output 
(33) must be replaced. 
7.5  Too small indication of pressure and/or temperature __________________________  
If the autoclave does not register the prescribed val-
ues for temperature and / or pressure because of an 
operator's mistake, a malfunction will reported in all 
cases (see Section 8). 
If the pressure gauge or thermometer indicates ex-
cessively low values although the program has been 
normally completed (lamp 
„
END“ (13) lights at con-
clusion of process), you must notify the MELAG 
Customer Service Department, and an engineer 
must check the instrument involved. 
However, if the values for temperature and pressure 
are slightly too low but do correspond, the tempera-
ture sensor for steam (screwed into the steam chan-
nel of the vessel block from the bottom) has to be 
checked for resistances on plugs, and contacts may 
have to be cleaned or the sensor to be replaced. 
For questions about the precision of pressure gauge 
or thermometer refer to chapter 5.2. 
7.6  Excessive indication of pressure and/or temperature __________________________  
A short rise of pressure up to 2.3 bar, shortly before 
the beginning of a sterilization, that is just before the 
"Running" light changes from blinking to constant 
lighting, serves for a minimization of the equalization 
time and for a proper ventilation of the instruments' 
inner parts. When regulation starts, pressure falls 
down to approximately 2.1 bar. On principle, the 
thermometer should indicate values not higher than 
137°C. 
If pressure rises to over 2.4/0.4 bar for a short time, 
but falls down again to values of 2 and 2.1 bar (0.2 
and 0.3 bar), call for a service engineer
 who has to 
adjust the pressure switch inside of the autoclave. 
7.7  Hissing during run / foggy instruments______________________________________  
If you can clearly hear a hissing noise at the sliding 
door after a program was started, either the seal is 
dirty, damaged or the sliding door was pressed 
down during locking which causes an overturn of the 
vessel's lip. For this reason, steam can escape 
through the resulting gap. 
A damaged seal has to be replaced (seal is in a ring 
groove) and in case of overturned seal, the sterili
zation process can be stopped by switching off the 
main switch. After pressure drop, open sliding door 
and once again close it correctly (do not press down 
while closing). 
A dirty seal can be cleaned with alcohol on a fluff 
free cloth. If the sliding door itself is dirty, put a thin 
cloth on top of the vessel, close the sliding door and 
open it again. See also chapter 2.3. 
 





 
 
page 24 
7.8  Sliding door cannot be unlocked ___________________________________________  
Pressure operated lock of sliding door (1) 
As soon as the autoclave has reached a pressure of 
0.2 bar, a bolt enters the locking mechanism of the 
sliding door and prevents its opening during proc-
ess. After the pressure drops to "0", this bolt re-
leases the locking mechanism so that the sliding 
door can be unlocked by a 90° turn counter-clock-
wise and be pushed back (marking on knob is now 
along with the apparatus' axis), see also chapter 4.5. 
If you try to open the door before pressure is 0 bar, 
you will not succeed because the bolt is still locked 
in. Thus, the sliding door cannot be completely un-
locked and opened. 
In this case, lock the door once again (marking is 
now crosswise with the apparatus' axis), wait until 
pressure drops to "0" and then unlock and open the 
door. 
If the sliding door still cannot be opened, then it is 
jammed by long instruments which protrude too far 
upward -- or the mechanical system of the door is 
defective. Try to slide the door backward by applying 
slightly more force. 
You must notify the MELAG Customer Service De-
partment. 
Pressure release takes too long 
During normal operations, the pressure indication 
has fallen to 
„
0“ by the time the lamp 
„
END“ (13) 
glows and the acoustic signal sounds. If, however, 
an extremely great number of unpacked metal in-
struments are sterilized together, then re-
evaporation of the resulting condensate can cause a 
situation in which the operator must wait a few sec-
onds after the acoustic signal before the pressure 
has completely fallen and the door allows itself to be 
opened (as described above).  
When the pressure gauge shows a value of 0.2 bar 
or more at the end of a cycle (light 
„
END“ (13) glows, 
with a beep), there is dirt inside the apparatus which 
has settled down to the steam filter in front of the so-
lenoid valve of the pressure release (41). 
This filter can be reached from the lower side of the 
autoclave without dismantling it (use a spanner with 
14 mm). 
The filter must be cleaned by a service engineer
 or 
replaced. During this service work, the adjacent 
openings should be rinsed and blown out before the 
autoclave is reassembled. To perform this, first re-
move the filter, then close off the outgoing-water 
hose to prevent water from flowing through it. Then 
pour demineralized or distilled water into the pres-
sure vessel and allow it to run through. Then close 
the sliding door, and blow through the outgoing 
waste water hose. 
7.9  The sliding door cannot be easily moved ____________________________________  
Normally, the sliding door (1), when unlocked -- see 
Section 4.5 -- can be very easily moved: for exam-
ple, with 2 fingers. This is because of the following: 
the actual metal closure floats over the door gasket, 
the door slides on PTFE bearings, and the door 
moves into a recess at the rear area of the auto-
clave. If the door, however, is difficult to move, 
please consider the following possibilities: 
Transport damage 
If the autoclave has been subjected to violent impact 
from the side during transport, it is possible that the 
suspension of the upper autoclave plastic cladding 
has been bent. In this case, it is possible that the 
collar of the cladding of the sliding door (under the 
locking handle) collides toward the rear with a cor-
ner of the opening in the upper part of the autoclave 
cladding. You must notify the MELAG Customer 
Service Department. The technician must adjust the 
suspension of the upper autoclave plastic cladding 
in order that the collar runs properly in the centre of 
the opening. 
The metal closure cover does not completely lift 
during unlocking. 
If the actual metal closure cover (5 mm thick) does 
not lift, or completely lift, although the door is fully 
unlocked, then the closure will not float over the gas-
ket and its upper side will not lie flush at the upper 
corner of the guide slot. The operator can then pro-
visionally lift the closure by pressing on the plastic 
cladding of the sliding door, and by pulling on the 
locking handle, and can then open the autoclave. 
You must notify the MELAG Customer Service De-
partment. 
The problem may be that a technician has forgotten 
to reinstall the PTFE bearing pieces between the 
closure cladding and the slide rails after a repair job. 
Or, the 4 spring-loaded hexagon socket-heat screws 
have jammed because of soiling, debris from paint, 
or a crooked position in the guides of the closure 
cladding. In such case, unscrew the screws, clean 
the guides, and screw the screws back in tight by 
hand, using the springs and a thread-locking adhe-
sive.
7.10  Water reservoir goes empty _______________________________________________  
If the water gets from the reservoir to the condenser 
container and thus gets empty (over night), there is 
a leak in the non-return valve of the pump. 
Inform the service engineer
 who will clean or replace 
the pump. 
The autoclave can be used in the meantime, if the 
cycle successfully runs the end: i.e., if the lamp 
„
END“ (13) lights up. 
 





 
User Manual 
MELAquick
®
12
 
page 25 
8  Fault with warning light 
The following hints should give you the possibility to 
correct small faults or to give an exact description of 
the fault to the service engineer. Because the ME-
LAquick12
® 
 indicates the cause of fault in a special 
way, it is possible to treat faults according to the ta-
ble below. 
In any case, you must report the following data 
to the MELAG Customer Service Department:  
•  The point in time when the malfunction was re-
ported (for example, during the preheat phase, 
during pressure generation, or during the sterili-
zation period).  
•  The LED signal which reported the malfunction. 
•  The values for pressure and temperature indi-
cated at this time. 
•  Any unusual developments (for example, re-
peated starting of the water pump). 
The MELAG Customer Service Department requires 
this information in order to quickly repair the auto-
clave at a cost economical to you. 
 
 
Fault 
No. 
LED 
Fault 
LED 
Door 
LED 
Water 
LED 
Ready 
LED 
Run 
Cause and time of fault 
1  blinks      off    Supervision time for pre-heat exceeded, happens 
during pre-heat phase ("Ready" blinks) 
4  blinks      off  blinks  Supervision time for pressure generation exceeded, 
happens during pressure generation ("Running" 
blinks) 
5  blinks      off  blinks  Supervision time for sterilization time exceeded, hap-
pens during sterilization ("Running" lights) 
9  on  blinks        Attempt to unlock sliding door during process 
11  on      blinks  blinks  Maximum steam temperature exceeded after auto-
clave was once "Ready" 
15  on  blinks    off  blinks  Power failure during the last cycle 
 
 
In every of the above cases and in case of "normal" 
misoperation (pressing "start" button when autoclave 
not "READY" or process already running), you will 
hear a beep for 2 seconds. On principle, you 
should observe type and time of the fault (e.g. 
during pre-heat phase or during pressure gen-
eration or during sterilization) and inform the 
service engineer in order to make a quick and low-
priced repair possible. 
The autoclave has to be repaired only by the 
manufacturer or by an authorized engineer. 
8.1  Fault No. 1______________________________________________________________  
Cause of the fault: 
The autoclave's vessel has not reached the neces-
sary pre-heat temperature within the supervision 
time of 25 minutes (sterilization), 15 minutes (disin-
fection) respectively. 
Time of fault: 
During pre-heat phase (lamp "READY" blinks) 
Call for a service engineer.
 
Diagnosis of fault: 
1. If the vessel is warm during fault indication and 
the apparatus indicates "READY" after you have 
switched off 
„
main“ switch and on again shortly 
and waited for a few minutes, there is at least 
one heating cartridge of the pre-heating defec-
tive. 
2.  If the vessel does not get warm, a fuse has failed 
or a plug contact is defective. 
3. If the vessel heats up to approximately 150°C 
(temperature of the overheat protection), there is 
a short circuit in the temperature sensor of pre-
heating. 
Fault correction: 
1.  Measure and replace heating elements. 
2.  Measure pre-heat output of the electronic and re-
place defective elements. In case of defective 
fuse, you must also check the function of elec-
tronic exits. The semiconductor-relay should only 
switch if output was directed (e.g. by test knob, 
lower left side of the electronic plate). This can 
be noticed by the respective lamp of the output. 
Otherwise, the relay is defective and the elec-
tronic print has to be replaced. 
  If somebody had been working on the autoclave 
before, you should check whether the cable 
shoes of the temperature sensors are sitting on 
the right connector (pre-heat sensor to upper 
connectors). Measure resistance values. 
3.  If there is a short circuit in the temperature entry 
of the pre-heating, the vessel will heat up to 
150°C until overheat protection is released, with-
out a light of lamp "READY" because the resis-
tance for pre-heat temperature cannot be 
reached. Replace sensor. 
 





 
 
page 26 
8.2  Fault No. 4______________________________________________________________  
Cause of fault: 
The autoclave did not achieve its parameter for 
pressure and/or temperature within the supervision 
time of 5.5 minutes. 
Time of fault: 
After program start, during pressure generation 
(lamp "READY" blinks). 
The following reasons can be given: 
8.2.1  Autoclave insufficiently ventilated _________________________________________________ 
In this case, the water pump runs only once after 
the start of the program. 
For proper function of the autoclave (death of 
germs), it is necessary to extract air, respectively 
air/steam-mixture, out of the vessel. After a program 
start or during pressure generation, air is extracted 
through a current channel which branches off in the 
rear part of the vessel, leads to the measuring block 
and then thron a fine filter to the inside current 
jet (43). In this channel the steam-temperature sen-
sor for the electronic system (35) (visable from 
above in the rear opening of the pressure-vessel 
bottom, under the sieve insert for the pressure ves-
sel), as well as the temperature sensor of the ther-
mometer (39), are contacted by the flowing steam. 
In front of the hose connection to the measuring 
block is an additional steam filter screwed inside the 
vessel block (44). 
Fault diagnosis: 
The autoclave will not properly vent if any of the fol-
lowing components are clogged: the sieve insert for 
the pressure vessel, the fine filter installed upstream 
of the nozzle (43), or the steam filter (44). The auto-
clave does achieve a pressure of approx. 2.2 bar 
(for sterilization), or 0.3--0.4 bar for disinfection 
within a period of 1.5...3 min. after the start of the 
program. Although it maintains this pressure, an ex-
cessively 
low temperature (or no temperature at all) is indi-
cated on the thermometer. The autoclave then 
switches over to fault no. 4 after program start, since 
the partial pressure of the air is added to that of the 
steam, which prevents the saturated-steam tem-
perature from being achieved at the prescribed 
pressure. 
Call for a service engineer.
 
Beyond, every blockage in this area can be reco-
gnised with the transparent Teflon hose which leads 
from the measuring block to a T-junction. In this 
hose (and thus in the water discharge hose), you 
can normally see small amounts of flowing 
steam/condensat. The presence of prescribed tem-
perature (134°C/105°C) will additionally be indicated 
by an internal LED of the electronic regulation unit. 
Fault correction: 
Remove the sieve insert. Optical control of ventila-
tion hole in the vessel (bottom of vessel at rear rim). 
This hole should not be covered or blocked. Check 
whether somebody has worked without sieve insert 
so that instruments have covered the ventilation 
hole. 
Check jet (43) and filters (40) and (44), if necessary 
also steam filter (34), probably clean or replace 
them. Before complete re-assembly it might be use-
ful to run the autoclave once without fine filter (40) 
and jet (43) to flush the tubing system and remove 
any residues. 
8.2.2  Pressure switch is wrongly adjusted/defective _______________________________________ 
In this case, the water pump runs only once after 
the start of the program. 
Diagnosis of fault: 
If the autoclave achieves a pressure for sterilization 
of less than 2.1 bar (or 0.2 bar for disinfection) within 
1.5 ... 3 min., if it remains at this insufficient pres-
sure, and if the thermometer reaches the corre-
sponding saturated-steam temperature, then the 
pressure switch for sterilization (53) or for disinfec-
tion (54) is not properly set -- or, it is defective. 
The autoclave indicates fault no. 4 without a repea-
ted start of the pump because the prescribed super-
vision temperature cannot be achieved. 
Call for a service engineer.
 
Fault correction: 
Adjust the respective pressure switch by turning the 
justification screw clockwise so that during pressure 
generation, a pressure of 2.25...2.3 bar 
(0.3...0.4 bar) will be reached. If the adjustment has 
no success, replace the pressure switch. 
The autoclave must be placed in the pure pressure-
control mode in order to adjust the pressure switch. 
To make this adjustment, first switch off the power 
switch (4). Then hook in the two upper wire-clasp 
switches (A and B) of the 4 wire-clasp buttons / 
switches (32) on the electronic circuit board, at the 
lower left on the circuit board (on a blue plastic 
base). The second switch from the top has already 
been hooked in at the factory. After adjustment work 
is completed, make sure that the power switch is off, 
and unhook the upper wire-clasp switch (A). If ad-
justment is not possible, the pressure switch must 
be replaced, and the new switch must be properly 
adjusted. 
8.2.3  Failure of the heating for steam generation__________________________________________ 
In this case, the water pump runs only once after 
the start of the program. 
Fault diagnosis: 
If the autoclave does not build up any pressure while 
lamp "RUNNING" is blinking and the steam genera-
tor under the vessel does not get warm, a fuse has 
failed or a contact or the electronic regulation unit is 
defective. 





 
User Manual 
MELAquick
®
12
 
page 27 
Call for a service engineer. 
Check output of steam generator, fuse and steam 
generator itself. 
Fault correction: 
Replace defective element. In case of defective 
fuse, check the output of the electronic. The semi-
conductor relay should only operate when the exit is 
directed (e.g. by test knob). You can observe its op-
eration by the light of the respective LED of output 
on the electronic circuit. Otherwise, the relay is de-
fective and the electronic must be replaced. 
8.2.4  Short circuit of the temperature sensor for steam ____________________________________ 
In this case, the water pump only once after the 
start of the program. 
Fault diagnosis: 
The autoclave reaches a pressure of approximately 
2.2 bar (sterilization), respectively 0.3-0.4 bar (disin-
fection) within 1.5 to 3 minutes after a program start 
and keeps the pressure constant, but indicates fault 
No. 4 after 5.5 minutes. The thermometer monitors a 
temperature of 135°C (105°C) which means that the 
current jet is clear. 
Call for a service engineer.
 
Fault correction: 
Check temperature sensor for steam (screwed into 
the current channel of the vessel block from under-
neath) and replace it. 
8.2.5  Too small dose of water__________________________________________________________ 
In this case, the water pump runs several times 
after the start of the program. 
After a program start, the pump must get into action 
and, in the required pumping time of 16 seconds, 
about 150 ml of aqua dest/aqua dem must be raised 
from water reservoir to the steam generator. 
Fault diagnosis: 
If this water dose is too small, the pump will start 
again at release of the steam generator's overheat 
protection and after the end of the real pumping 
time. Thus, the correct supervision times for pressu-
re generation and killing may be exceeded. 
You must notify the MELAG Customer Service De-
partment. 
To check the amount of raised water, loosen the 
hose connection from pump to vessel block at the 
vessel block, put the hose's end into a measuring 
beaker and start the pre-warmed apparatus. After 
16 seconds, the pump must stop with an amount of 
water in the beaker between 130 and 170 ml. After 
this pumping time, immediately switch off the auto-
clave, otherwise the pump will start again due to 
overheat of the steam generator (in order to avoid 
this during the test, you can remove a cable shoe of 
the steam generator). 
If there are deposits of scale on the top side of the 
disassembled hose, then it is necessary to clean 
both this hose as well as the steam generator. See 
Section 8.2.7. 
Fault correction: 
1. If the water pump (47) does not start, then the 
following must be checked: the fuse for the out-
put for the pump, the cable connections, the 
thermalprotection element installed on the pump 
(a bimetallic trip), and the pump itself if required. 
2. When the amount of water is too small, loosen 
silicone hose on the suction side of the pump and 
look if water runs out freely. 
  If insufficient water runs out, or no water at all, 
check to see if the hose is clogged (clogging can 
perhaps take place in the water storage tank), 
and /or change the water filter if required. 
  Finally, check to make sure that a sufficient 
amount of water is being pumped. 
3.  If there is no blockage on the suction side of the 
pump and the amount of raised water is too 
small, the pump should be replaced. 
4.  If the water reservoir is empty, but the autoclave 
indicates no lack of water, check all cables and 
the pressure switch for level control, perhaps re-
place them. 
8.2.6  Too much loss of water __________________________________________________________ 
In this case, the water pump runs several times 
after the start of the program. 
Fault diagnosis: 
After a program start, the autoclave ventilates the 
vessel through the current jet which is screwed into 
the measuring block (see also chapter 8.2.1). Then 
steam constantly flows through this jet into the con-
denser container. The resulting loss of water is 
equalized by the amount of water supplied to the 
steam generator at the beginning of a process. If 
water gets lost beyond, this can happen due to en-
larged current jet, leak in the vessel seal (see also 
7.9) or at the solenoid valve, the safety valve or due 
to a loose coupling. 
If the steam generator is calcificated due to bad wa-
ter quality, the pump will also start again because 
the overheat protection of the steam generator re-
leases before heat reaches the water inside. 
The pump will start again at release of the steam 
generator's overheat protection and after the end of 
the real pumping time. Thus, the correct supervision 
times for pressure generation and killing may be ex-
ceeded. 
Call for a service engineer.
 
1.  If a loud hissing sound can be heard at the slid-
ing door while the autoclave is under pressure, or 
if the indicator instruments are fogged, then the 
cause is one of the following: either the gasket lip 
has been turned over by improper closing of the 
sliding door, or the gasket for the pressure vessel 
is defective. 
2. Otherwise, loosen the connection of the hose 
from the pump to the vessel block, bend hose 
into a measuring beaker without kinking it and 
start the pre-warmed apparatus. After 





 
 
page 28 
16 seconds, the pump must stop with an amount 
of raised water between 130 and 170 ml. Alterna-
tively, you can measure the weight of the con-
denser container before and after sterilization. 
The increase of weight must be 130-170g. 
  If there are deposits of scale on the top side of 
the disassembled hose, then it is necessary to 
clean both this hose as well as the steam gen-
erator. See Section 8.2.7. 
 
Fault correction: 
1. The gasket of the autoclave pressure vessel 
must be cleaned or replaced (see Section 2.3). 
2.  If the amount of water is too small, refer to Sec-
tion 1.1.1. 
  If the amount is correct, optically check all joints 
for leakage when they are under pressure. Watch 
the water discharge hose of the solenoid valve 
(short and straight Teflon hose from solenoid 
valve to a hose-T-junction, left side of the appa-
ratus). Here, no steam should flow. Observe dis-
charge hose of the safety valve (bent Teflon hose 
from ground plate to hose-T-junction, right side of 
the apparatus). Here, no steam should flow. 
  Tighten all joints, clean or replace magnetic valve 
or clean safety valve / replace inner parts. 
  If there are no such leakages, check the current 
jet and perhaps replace it. The diameter of the 
orifice should not be much larger than 0.5 mm. 
  If the problem is still not solved (but water supply 
is okay, no water loss) and the pressure genera-
tion operates slower than usual, check the steam 
generator for calcification. It must be cleaned or 
changed. 
8.2.7  Steam generator is clogged with boiler scale ________________________________________ 
In this case, the water pump runs several times 
after the start of the program. 
Fault diagnosis: 
The water pump (47) starts several times, although 
amount of the water is sufficient (see Section 1.1.1), 
and although there are no leaks (see 8.2.6). In addi-
tion, the upper side of the hose from the water pump 
(47) to the pressure vessel unit (37) is covered with 
scale. 
You must notify the MELAG Customer Service De-
partment. 
Correction of the fault: 
The hose and the steam generator must be cleaned 
or replaced if required. 
8.3  Fault No. 5______________________________________________________________  
Cause of the fault: 
After the autoclave has once achieved the steriliza-
tion or disinfection parameter for pressure and tem-
perature (as signalled by the lamp 
„
RUNNING“ 
(12)shining continusly), the system is not able to 
maintain these parameters for the required period of 
4 minutes for sterilization, or 6 minutes for disinfec-
tion, throughout the monitoring period of 5.5 minutes 
for sterilization, or 7.5 minutes for disinfection. 
Time when the malfunction occurs: 
After the start, and after 5.5 minutes (for sterilization) 
or after 7.5 minutes (for disinfection) after once 
achieving the sterilization or disinfection parameters 
for pressure and temperature (as signalled by the 
lamp 
„
RUNNING“ (12) shining continuously). 
The cause here can be as follows: 
8.3.1  The amount of water measured out is not sufficient / loss of water ______________________ 
In this case, the pump will start during the 
RUNNING phase but will later switch off again 
automatically. 
This malfunction will cause the pressure and the 
temperature to fall, which will in turn cause the lamp 
„
RUNNING“ (12) to flash and the metering of the 
sterilization time to stop. See Section 8.2.2 and 8.2.6 
for the cause of this malfunction and for ist correc-
tion. 
8.3.2  Interchange the temperature sensors_______________________________________________ 
Cause of fault: 
In this case, the parameters for pressure and tempe-
rature are reached after the program start but then, 
after a short time, pressure considerably falls down 
to less than 2 bar, without lamp "RUNNING" starts 
blinking again. 
You must notify the MELAG Customer Service De-
partment. 
Correction of the fault: 
Exchange connection cables of the temperature 
sensor on the electronic plate (temperature sensor 
for pre-heating, built in on the side of the vessel 
block, must be connected to the upper two small 
connectors; temperature sensor for steam tempera-
ture, screwed into the current channel of the vessel 
block from underneath, must be connected to the 
lower small connectors). 
8.4  Fault No. 9______________________________________________________________  
Cause of the fault: 
The autoclave releases a fault too, if you have tried 
to open the sliding door after the program started 
(indicated first by a blinking light of lamp 
"RUNNING" and then by a constant light). 
If this fault release happens independently, the jus-
tification of the door contact may be incorrect. 
Time of fault: 
After the program started and before lamp "END" 
lights. 
If this fault repeatedly occurs, although the autoclave 
is being correctly operated, then you must notify the 
MELAG Customer Service Department. 
Fault correction: 





 
User Manual 
MELAquick
®
12
 
page 29 
The setting of the door-contact rod must be checked 
after the autoclave has been preheated. If neces-
sary, the lock nut on the mircoswitch (50) must be 
unscrewed, and the position of the switch on the in-
side of the autoclave must be readjusted. After the 
readjustment has been made, the lock nut must be 
tightened again, and the switchpoint (the clickpoint) 
must be checked. The correct clickpoint is as fol-
lows: when the autoclave is preheated, and when 
the sliding door is locked, the microswitch should 
click approximately halfway through the travel of the 
door-contact rod. The total travel should be 2 mm. If 
the rod which activates the door contact has been 
damaged by violent pushing of the door while it is 
locked (i.e., the contact rod is bent in the guide), 
then this can also lead to malfunction. If the contact 
rod is bent, the microswitch must be removed, and 
the contact rod must be straightened. Then reinstall 
the switch, with the round side facing up, and prop-
erly adjust the door contact (see instructions above). 
 
8.5  Fault No. 11_____________________________________________________________  
Cause of the fault: 
The autoclave registers a steam temperature of 
140°C (sterilization), respectively 112°C (disin-
fection) which is too high. 
Time of fault: 
1.  After the pre-heat phase is over when lamp 
"READY" normally should change form blinking 
to a constant light. 
2.  During operational readiness (the 
„
READY“ 
lamp (11) is already lit). 
3.  During pressure generation, above 2 bar (ster-
ilization) / 0.3 bar (disinfection), just before 
lamp "RUNNING" (12) lights constantly. 
4.  After program started and before lamp "END" 
lights. 
You must notify the MELAG Customer Service De-
partment. 
Fault diagnosis: 
1.  If the fault already appears after the pre-heat 
phase, either the sensor for steam temperature 
is defective (resistance is too high or infinite) or 
the transfer resistance at the connecting places 
is too high or there is a loose sensor contact 
(infinite resistance). 
2.  In this case, the semiconductor relay of the 
output for the preheating system is defective. 
The preheating system continues to heat, al-
though the output has not been activated. As a 
result of thermal coupling (i.e., the temerature 
sensor is screwed into the preheated pressure-
vessel unit), a steam temperature of 140°C is 
registrated in this case. 
3.  If the pressure develops normally increase up 
to a maximum of 2.3 bar for sterilization or 
0.4 bar for disinfection), then the temperature 
sensor has a loose contact, or there is poor 
contact at the terminal. 
4.  The electronic circuit board has become moist 
as a result of a leak in the door gasket, be-
cause of the condensate (see Section 3.1), or 
because of the moisture which has entered the 
autoclave by another route. As a result, the 
contact resistance values have changed. 
Fault correction: 
1.  Clean sensor contacts, i.e. replace steam sen-
sors (screwed into the current channel of the 
vessel block from underneath). 
2.  Replace the semiconductors relay for the pre-
heating system, or replace the entire electronic 
circuit board. 
3.  Clean sensor contacts, i.e. replace steam sen-
sors (screwed into the current channel of the 
vessel block from underneath). 
4.  Allow the electronic control system to dry, or 
clean it with methylated alcohol (C
2
H
6
O). Re-
place if necessary. 
8.6  Fault No. 12_____________________________________________________________  
Cause of the fault: 
The autoclave will go into the malfunction mode 
when the quality (conductivity) of the demineralized 
or distilled water is so poor that the autoclave and 
the instruments could be damaged. (also see Sec-
tion 1.7). 
Time of the fault: 
Two seconds after pressing the 
„
START“ button (7). 
Correction of the fault: 
Drain the water out of the water reservoir (see Sec-
tion 5.3.2). Rinse out the water storage tank with 
demineralized or distilled water as described in Sec-
tion 5.3. Then fill again with adequate water (see 
Section 3.3). 
 





 
 
page 30 
8.7  Fault No. 15_____________________________________________________________  
Cause of the fault: 
The power switch was turned off during a program 
cycle, or there was an interruption of power to the 
autoclave. This fault will be printed out on the log 
only if the last log is printed out again (see Sec-
tion 1.5). 
Correction of the fault: 
Start the program and sterilize / disinfect the batch 
of the instruments again. 
 





 
User Manual 
MELAquick
®
12
 
 
9 Spare parts 
Article Description  Article Description 
30570  waste water hose 1.5 m (22)  31970  Sieve for steam filter (41) 
alternative 
39310 
waste water hose (give length)
 (22)  31160  Fine filter in the measuring unit (44) 
12550  vessel seal (below sliding door)  31465  water pump (47) 
34115 current jet (43)  38705  pressure switch sterilization (53) 
30720  ball for safety valve (42)  39695  pressure switch disinfection (54) 
31825 water filter (46)  40812  pressure switch water level (45) (since fabr no 94 12 213) 
31175  solenoid valve for pressure release (49) 30360  electronic regulation unit (since fabr. no. 94 12 5000) 
29570  coil for solenoid valve  30470  front panel w. electr. indication (since fabr.no. 94 12 5000)
39100  rectifier plug for solenoid valve  31140  plug for water discharge hose (19) 
31095 pressure gauge (5)  31530  lid for water reservoir (3) 
30640 thermometer (6)  30480  cover caps for door face 





 
 
 
BA_GB_MELAquick12.doc  Rev.: 8 – 09/1292  page 32 
 
Notes: