MELAG MELAtronic 23 User manual

User Manual
MELAtronic®23
Steam sterilizer
-Not for medical use / only for veterinary use-
Dear customer:
We thank you for your confidence demonstrated by the purchase of this MELAG product. As an owner-run
and operated family concern founded in 1951, we have a long history of successful specialization in hygiene
products for practicebased use. Our focus on innovation, quality and the highest standards of operational
reliability has established MELAG as the world’s leading manufacturer in the instrument treatment and hy-
giene field.
You, our customer are justified in your demand for the best products, quality and reliability. Providing "com-
petence in hygiene" and "Quality – made in Germany", we guarantee that these demands will be met.
Our certified quality management system is subject to close monitoring: one instrument to this end is our an-
nual multi-day audit conducted in accordance with ISO 13485. This guarantees that all MELAG products are
manufactured and tested in accordance with
strict quality criteria.
The MELAG management and team.
EN

2
User Manual MELAtronic®23
MELAG Medizintechnik GmbH & Co. KG
Geneststraße 6-10
10829 Berlin
Germany
E-Mail: [e-mail]
www.melag.com
Original instructions
Responsible for content: MELAG Medizintechnik GmbH & Co. KG
We reserve the right to technical alterations
BA_tronic23_10023_EN_v3.doc /Rev.: 3 – 20/0698
Modification date: 2020-05-05

MELAtronic®
23
The functional effectiveness and the preservation of the
value of this equipment will depend on:
•The proper preparation of the objects that you wish to sterilize
•The prevention of rust being introduced to the system from the
outside
•The careful care of the equipment
•The regular exchange of distilled or demineralized water.
Page
SAFETY INSTRUCTIONS / WARNINGS ..........................................................................................................4
1INTRODUCTION.........................................................................................................................................5
1.2 Technical data ......................................................................................................................................5
1.3 Preparation of instruments ...................................................................................................................6
1.4 Rust in the steam sterilizer: brought in from the outside......................................................................6
1.5 Care of the steam sterilizer ..................................................................................................................7
1.6 Instructions for checking and caring for the door and door-lock components .....................................7
1.7 Functional testing of the steam sterilizer..............................................................................................8
2PLACING THE STEAM STERILIZER INTO OPERATION ........................................................................8
2.1 Setting up the steam sterilizer..............................................................................................................8
2.2 Filling the water storage tank ...............................................................................................................9
3INFORMATION FOR EVERY STERILIZATION CYCLE............................................................................9
3.1 Objects being sterilized ........................................................................................................................9
3.2 The sterilization sequence .................................................................................................................10
3.3 Checking to ensure that the cycle has properly run...........................................................................10
3.4 Aborting the program .........................................................................................................................11
3.5 Removal of dry objects ready to use..................................................................................................11
3.6 Frequency of daily sterilization...........................................................................................................11
4ADDITIONAL INFORMATION ON STERILIZATION ...............................................................................11
4.1 Total operating time (sterilization cycle time).....................................................................................11
4.2 Using distilled or demineralized water................................................................................................12
5TROUBLESHOOTING..............................................................................................................................13
5.1 Trouble without an error report...........................................................................................................13
5.2 Malfunctions with error messages......................................................................................................14
6ANNEX / SPARE PARTS .........................................................................................................................15
6.1 Spare parts.........................................................................................................................................15

4
Safety instructions / Warnings
•Do not sterilize any liquids with this steam sterilizer. It is not approved for the sterilization of liquids.
In case of non-observance, the consequences could be delayed boiling, damage to the steam steri-
lizer and burns.
•The edge of the door, the edge of the sterilization chamber, and the sterilized objects become very
hot during operation.
•The door can also be opened during an active program. Never open the door during an active program.
Failure to observe these provisions could result in burns
•Do not open the door of the steam sterilizer until you are sure that there is no pressure inside. It is
safe to open the steam sterilizer if the pressure gauge shows “0”.
•After opening the steam sterilizer door, do not touch exposed hot metal parts. Use the MELAG Tray
Handle to remove hot trays, and use suitable heat-protection gloves to remove other sterilization con-
tainers.
•Drain the water out of the water storage tank before transporting the steam sterilizer. Do not tip the
steam sterilizer if there is water in its tank.
•The free movement of the safety valve rod must be guaranteed.
•This steam sterilizer may be repaired only by persons authorized by MELAG, and only with original
MELAG spare parts.
•Never open the enclosure of the steam sterilizer without first pulling the plug of the power cable.
•This steam sterilizer may not be operated in areas subject to explosion hazards
Placing the steam sterilizer out of operation / Transport instructions / Placing the steam ster-
ilizer back into operation
To place this steam sterilizer out of operation, and to transport them, observe the following:
•Pull out the plug of the power cable. Allow the steam sterilizer to cool down.
•Drain the water out of the storage tank by opening the drain plug (16).
•If you transport the steam sterilizer while the tray racks and/or the trays themselves are still inside, you
must protect the polished door of the steam sterilizer from being damaged. Place foam rubber between
the racks or trays and the door: or use some other suitable material such as Bubble Wrap®.
•Two people are necessary to carry the steam sterilizer by lifting it from below. Failure to observe this can
result in spinal damage or contusions.
•When you place the steam sterilizer back into operation after moving or repairing it, follow the instructions
given in Section 2, “Placing the steam sterilizer into operation”.
Important: To avoid damaging the steam sterilizer during transport, be sure to use its original packaging.
Symbols on the
steam sterilizer
Meaning
Explanation
Health hazard
Indicates a hot surface or hot steam which could be emitted from
the aperture marked.
Health hazard
Indicates the necessity to observe the safety instructions con-
tained within the user manual before operating the steam steri-
lizer.

MELAtronic®
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5
1 Introduction
1.1 Elements on the front of the steam sterilizer ______________________________
1
Enclosure lid
6
Switch for water feed
12
Lamp for “Heating on”
2
Grating rack to hold the trays,
etc.
7
Power switch
13
Lamp for “Cycle is running”
8
Display
14
Opening to check for water filling
3
Pressure gauge
9
Button to turn drying on
15
Adjustable feet of the unit
4
Switch program selection
10
Button to turn drying off
16
Drain for distilled water
5
Switch to start program
11
Show remaining run time /
cancel error message
1.2 Technical data _______________________________________________________
1.2.1 Dimensions and times
MELAtronic 23
Device dimensions (WxHxD) 50 x 37 x 54 cm
(depth incl. door lock 66 cm)
Chamber ( ∅×depth),
23 ×45 cm
Chamber volume
19 l
Weight (empty)
26.7 kg
Loading capacity (incl. trays):
Instruments
4 kg
Textiles
500 grams unwrapped or wrapped in paper, or
300 grams in sterilization containers
Feed water per sterilization cycle
400 ml
Parameters for Program 1 (121°C)
121 °C, 1 bar, 25 min sterilization time
Parameters for Program 2 (134°C)
134 °C, 2 bar, 5 min sterilization time
Complete cycle time:
Program 1
35-45 min
9
1
2
3
4
5
6
11
7
8
10
12
13
14
15
15
16

6
Program 2
20-30 min
Drying time
Can be selected as required
Waiting time between two cycles
15 min
1.2.2 Power consumption and fuses
Type
Voltage
Power supply
Current
Fuse
art. no. for fuse
MELAtronic 23
220-240
V*
2000 W 8.7 A (230V: 8.7 A) 12.5 A slow 12690
110 V
1600 W
14.6 A (120V: 15.9 A)
20 A slow
57593
*max. voltage range 207-253 V
1.3 Preparation of instruments_____________________________________________
MELAG non-rusting materials
All parts of MELAG steam sterilizers that come into
contact with steam are made of non-rusting materials.
The sterilization chamber, the water tank, and the tray
rack are made of stainless steel. The steam lines are
of copper; the sterilization-chamber door, of chrome-
plated brass; and the trays, of anodised aluminium.
Rust dragged in from the outside
The use of these materials means that the steam ster-
ilizer itself cannot produce rust. When rust does at-
tack the steam sterilizer or sterilized objects, investi-
gations have always consistently that this rust is
dragged in by instruments when they enter the steam
sterilizer. It must be remembered that even stainless-
steel instruments from leading manufacturers can de-
velop rust: for example, after improper treatment with
chemical cleaning and disinfecting agents during in-
strument preparation.
Preparation of the objects to be sterilized
The problem of rust dragged in from the outside
shows how important it is to properly prepare the ob-
jects to be sterilized. The following preparation in-
structions are absolutely essential to ensure proper
sterilization:
After instruments are used, they must immediately be
disinfected and cleaned in a disinfection and/or clean-
ing agent, according to UVV/VBG 103. Be sure to use
the correct dosage of the agents, and to leave the in-
struments in the solution for the prescribed length of
time. We also recommend using such aids as ultra-
sonic devices and thermal disinfectors.
Important: It is essential that the instruments be
properly cleaned before disinfection, to avoid debris
separating from the instruments under steam pres-
sure and clogging the nozzles and valves of the
steam sterilizer. Latches, catches, joints, and hinges
must especially be cleaned very thoroughly with a
brush. Completely rinse off cleaning and disinfecting
agents under running water, while using a brush, be-
fore putting the instruments into the steam sterilizer.
Warning: Do not by any means allow any residue of
chemical substances from cleaning and disinfecting
agents to enter the steam sterilizer, since they will
cause corrosion. As last step, finally rinse the instru-
ments with demineralized water, dry them carefully,
and place them into the steam sterilizer.
New instruments being sterilized for the first time
The above-described cleaning procedure must also
be used for brand-new instruments, since they often
carry small amounts of oil, grease, and debris from
their production processes.
1.4 Rust in the steam sterilizer: brought in from the outside ____________________
As described above, this steam sterilizer itself cannot
rust owing to the kind of materials of which it is made.
Any rusty spots in the steam sterilizer are “dragged-
in rust”: from instruments or other metal objects with
rusty spots. This can occur on standard steel whose
electroplating is damaged, or even on stainless-steel
objects. Often, only one single rust-emitting instru-
ment is enough to cause rust to develop on other in-
struments or in the steam sterilizer. Dragged-in rust
will then transfer to other instruments or parts of the
steam sterilizer, and will spread from there. This is
why the sterilization chamber must be regularly wiped
out to prevent dragged-in rust from remaining on the
surface and further developing. Dragged-in rust must
be removed from the sterilization chamber, the water
tank, and from the tray rack. We recommend using
stainless-steel cleansers such as product Sidol or an
equivalent. Warning: Do not use steel wool or steel
brushes. To clean the sterilization chamber, first pull
the tray rack out of the chamber. Important: Do not
sterilize rusty instruments.

MELAtronic®
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7
Important:
The hinge bolts must by all means re-
main inserted com
pletely in the latch
and in the hinge yoke of the pressure
locking bar (left side). The bolt must
be flush as shown.
1.5 Care of the steam sterilizer_____________________________________________
Required each week
Cleaning of the chamber
You must clean the chamber and the door seal on the
chamber at least once a week. First take out the trays,
and then pull the tray rack out of the chamber. Wipe
out the chamber with a soft cloth or sponge. For stub-
born stains, use stainless-steel cleaner such as Sidol.
Caution: Make sure not to let such cleaning agent
enter the piping that leads out of the sterilization
chamber. Also wipe only in the direction of the surface
structure. Do not use steel brushes or pot cleaners
made of metal. The cleaning agents must not contain
chlorine, and must not be alkaline. You can remove
spots from stainless steel by using a 5% solution of
oxalic acid.
Door gasket
Check the door seal once a week for damage. Clean
the seal with normal, commercially available liquid
cleansers.
Every two weeks
The water tank (for distilled or demineralized water)
Every two weeks, drain the distilled or demineralized
water from the tank by opening the drain cock (16).
Clean the water tank if necessary: for example, with
a bottle brush, warm water, and a grease-cutting
agent. Rinse out with water and fill with fresh distilled
or demineralized water (see Section 4.2 for water
quality).
1.6 Instructions for checking and caring for the door and door-lock components ___
In order to prevent premature wear, the threaded spindle of the palm grip hand knob, as well as the hinges of
the latch yoke and the door locking bar, must always be kept well greased. We recommend plain-bearing
grease (MELAG article no. 24355), silicone grease, or Molykote.
The following drawings indicate trouble that may occur and that may be the result of excessive wear on the
door locking system. If any of these difficulties occur, inspection will be necessary by a MELAG Customer
Service representative, or by an authorized technician from a specialist dealer.
•Excessive play in the hinge of the
latch yoke
•
Excessive play in the
threaded spindle of the
palm grip hand knob
(rattling of the spindle in
the latch)
•
Definite difficulty in turn-
ing the threaded spindle
•
Excessive play in the hinge
of the pressure locking bar
(the door “hangs”)
If this bolt moves up or downward and is no longer
flush with the yoke (as shown in proper position in
left drawing), do not use the
steam sterilizer
. It must
be repaired by Technical Customer Service person-
l
•Hard-metal screw-thread insert has
been screwed out of the latch.

8
1.7 Functional testing of the steam sterilizer _________________________________
Regular checks
The microprocessor control for the MELAtronic auto-
matically monitors sterilization temperature and time.
You can check the pressure gauge during sterilization
(white pointer). After sterilization, the red non-return
(slave) pointer will show the maximum pressure
reached. If there is no error message in the display at
the end of the program, and if the red non-return
pointer is between 1 and 1.3 bar for Program 1
(121°C) or between 2 and 2.4 bar for Program 2
(134°C), and if the loading instructions have been cor-
rectly observed (see Sections 3.1 and 3.2), then you
can assume that effective sterilization has taken
place.
Periodic checks (every six months)
German standard DIN 58 946, Part 8, Section 3.2,
recommends:
“Period testing should take place at the site of use, at
recommended intervals of six (6) months. The pur-
pose of testing is to verify that the small-size sterilizer
effectively sterilizes upon observance of operating in-
structions.”
Hygiene institutes and state medical laboratories will
provide test spores upon request. They analyse these
spores and provide test results on a test form.
DIN 58 946, Part 4 and DAB 10 (official German Phar-
macopoeia), stipulate that Bacillus Stearothermophi-
lus spores (for example, the product ATCC 7953, Pa-
per Spore Strips, supplied by the company Oxoid, Cd.
number BR 23), must be used to test steam steam
sterilizers.
As stipulated, five bioindicators (plus a positive sam-
ple) are necessary to test the MELAtronic 23 (cham-
ber volume > 5 dm³), in accordance with
DIN 58 946, part 8.
If the test spores already are already packed (for ex-
ample, spore strips in paper packs, test tubes, or the
product Attest), do not pack them again in addi-
tional enclosures when you place them in the steam
sterilizer.
When conducting a spore test, the most stringent ste-
rility precautions are necessary to prevent re-contam-
ination. For example, after sterilization do not pack
the spore packets into the same envelopes used to
send them to you. Also do not use the same tweezers
after testing as before. We recommend sterilizing the
tweezers along with the test spores. To avoid falsify-
ing your results in making your analysis, do not allow
the non-sterilized positive sample to come into con-
tact with the sterilized test spores. For transport pur-
poses, you can also submit your positive sample in a
paper package that you have also sterilized.
Important note:
If the test spores are in a tube that is perforated only
on one side (for example, the product Attest by 3M),
then observe the following:
Never place these tubes into the steam sterilizer with
the perforation pointing upward (with Attest, the per-
foration is in the brown closure cap). Since this steam
sterilizer functions by the gravitation principle, the
perforation should ideally point downward: but at least
toward the side (as is the case for tubes).
If you are using “handmade” test-spore products that
are directly sealed in a paper-film package, then en-
sure that the paper sides are freely exposed to the
steam. The paper sides of the package should like-
wise point to the side or downward.
2 Placing the steam sterilizer into operation
2.1 Setting up the steam sterilizer __________________________________________
Electrical connection
The steam sterilizer must be powered from a sepa-
rate circuit. This circuit must be additionally protected
by a quick circuit breaker.
Open intervals to the sides
The steam sterilizer must be set up with an open in-
terval of at least 10 cm from the nearest walls. The
open space above the steam sterilizer should be at
least 30 cm. It is very important for proper sterilization
that the steam sterilizer be correctly set up. The fol-
lowing instructions must therefore be very carefully
followed: both for the first installation, as well as for
any change in location.
Correct setting up of the steam sterilizer
This MELAG steam sterilizer uses its own, direct
supply of water. This convenience makes it very im-
portant that the steam sterilizer operate on a per-
fectly level surface. Please use a spirit level (water
level) to properly level the steam sterilizer. To ena-
ble proper alignment of the steam sterilizer, MELAG
supplies a graduated measuring beaker with every
steam sterilizer. To check whether the steam steri-
lizer has been properly levelled, use this graduated
measuring beaker to fill the following amounts of dis-
tilled or demineralized water from the front into the
sterilization chamber: 400 ml.
If the steam sterilizer has been correctly aligned, the
water filled into the unit will just be visible at monitor-
ing section (14) of the tray rack. If the water is not
visible as described above, turn the front adjustable
feet of the steam sterilizer (15) until the steam steri-
lizer is properly levelled, and the water is just visible.
Important: When putting the steam sterilizer into
operation for the first time, be sure first to run the
134°C sterilization cycle once without any objects
in the sterilization chamber.
Incorrect: setting up on a surface sloping toward
the front of the steam sterilizer
If you try to install this steam sterilizer on a surface
that slopes to the front of the steam sterilizer, the dis-

MELAtronic®
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9
tilled or demineralized water will already become vis-
ible at the front of the sterilization chamber, through
the opening to check for water filling (14), before
enough water has flowed in. This means that there
will not be enough distilled or demineralized water to
achieve the proper pressure of 2 bar in the chamber,
and for this pressure to be maintained approx. 5 min.
– or that a pressure of 1 bar cannot be maintained
constant for the required time of action of 20 min.
Incorrect: setting up on a surface sloping toward
the rear of the steam sterilizer
If you try to install this steam sterilizer on a surface
that slopes toward the rear of the steam sterilizer, the
distilled or demineralized water will become visible at
the front of the sterilization chamber, through the
opening to check for water filling (14), after too much
water has flowed in. The excess water not consumed
during sterilization will then remain in the chamber
(which, however, will not impair steam sterilizer func-
tions).
2.2 Filling the water storage tank ___________________________________________
Take off the enclosure lid (1) on the housing of the
steam sterilizer, and then remove the cover of the wa-
ter storage tank.
Fill the water tank with approx. 3 litres of distilled or
demineralized water. Do not fill above the line marked
“MAX”. Make sure that the cooling coils in the water
storage tank are always covered with wa-
ter. This will allow the outstreaming steam to con-
dense, will prevent unpleasant steam effects, and will
reduce the consumption of distilled or demineralized
water. For this reason, always keep the level of water
filled above the coils. Or, better, drain off the remain-
ing water through the drain for distilled water (16), and
then fill up to the “MAX” level with distilled or demin-
eralized water.
3 Information for every sterilization cycle
3.1 Objects being sterilized _______________________________________________
Tray racks must be used
To prevent the danger of overheating of the sterilized
items by the heat radiated from the sterilization cham-
ber, this steam sterilizer must not be operated without
using a closed MELAG tray rack. These trays, other
supports on which the sterilized items are placed, and
containers for these items (with or without covers)
must be perforated.
Sterilization packages
The items for sterilization can also be sterilized in
sealed see-through sterilization packaging: for exam-
ple, MELAfol (with one side paper and one side trans-
parent film). During sterilization, the paper side of the
packs must face downward. These packs must not be
placed on top of each other on a tray. For better dry-
ing, we recommend lining up the see-through sterili-
zation packs vertically, like cards in a card-file box: for
example, in a MELAG Package Holder (MELAG arti-
cle no. 00283). When sealing the sterilized items in a
package, make sure that the sealing seams are at
least 8 mm wide (as stipulated by DIN 58953). The
MELAG MELAseal 100/101 Package Sealing De-
vices produce a sealing seam 10 mm wide.
Sterilized items that are sensitive to heat
IMPORTANT: When sterilizing plastic articles,
make sure not to exceed the maximum steriliza-
tion temperature as given by the manufacturer. By
no means allow heat-sensitive products (such as den-
tal aspirator tubes) to come into direct contact with the
tray rack of the steam sterilizer. The rack becomes
very hot from the heat radiated from the sterilization,
and this can damage such sensitive items.
Always place plastic articles (such as aspirator tubes)
on the middle tray. We recommend not placing heat-
sensitive items directly onto the steam sterilizer tray,
but on a sheet of filter paper.
Liquids
Warning: This steam sterilizer is not suited for the
sterilization of liquids.

10
3.2 The sterilization sequence _____________________________________________
1. Switch on the power switch
Switch on the steam sterilizer by the power switch
(7). The steam sterilizer will then test the electronic
systems and will display the interior temperature
of the sterilization chamber.
PLEASE NOTE
When switching off the device via the power
switch, wait three seconds before switching
it back on.
2. Reset the red non-return (slave) pointer
Set the red non-return (slave) pointer of the pres-
sure gauge (3) to “0”.
3. Load the steam sterilizer
Loosely load the trays or the sterilization contain-
ers with the objects to be sterilized, and slide in.
“Loosely” means the following, for example: do not
load textiles that are tightly folded, and do not
tightly press them into the sterilization containers.
Do not load more items than allowed (see Tech-
nical Data for limits).
4. Select the sterilization program
Use the switch for program selection (4) to choose
the desired program.
Use Program 1 to sterilize heat-sensitive objects
(of rubber, textiles, etc.) at 121°C.
Use Program 1 to sterilize bulky instruments (of
metal, glass, etc.) 134°C.
5. Fill the water
Set the switch for water feed (6) to “I” (green lamp
now shows) and wait until the water becomes vis-
ible at the opening to check for filled water (14).
When it becomes visible, set switch (6) to “0”.
6. Close the door
Close the door. Swivel the latch over the door lock-
ing bar, and lock the door by tightly screwing down
the palm grip hand knob.
7. Start the program
Start the program by pressing the Start button (5).
The display (9) will briefly confirm the program
start by showing “Run”. The lamp for “Cycle is run-
ning” (13) and the lamp for “Heater is on” (12) will
show at the same time.
8. Program run
The program will now run fully automatically. The
display will continuously show the steam temper-
ature in the sterilization chamber. After the air-re-
moval phase (approx. 15 min; temperature ap-
prox. 100°C), the heating-up time will follow. The
pressure and temperature will rise to the parame-
ters required by the specific program. When the
minimum temperature is reached (121 °C for Pro-
gram 1 and 134 °C for Program 2), the actual ster-
ilization phase will begin. The sterilization time will
now begin to run: 20 min for Program 1, and 5 min
for Program 2. To find out how much time remains
in the current sterilization run, press the time but-
ton (11).
During the sterilization period, the steam sterilizer
control system will maintain the sterilization tem-
perature for Program 1 at 122°C and for Program
2 at 136°C.
9. End of the sterilization cycle
At the end of the sterilization cycle, quick pressure
release will automatically take place. The lamps
for “Heater is on” (12) and “Cycle is running” (13)
will go out.
10. Open the door
Check the pressure gauge to make sure that the
pressure has been completely released. Then you
can safely open the door.
11. Drying and removing the sterilized objects
If the sterilized objects are wrapped, you must
leave the steam sterilizer door slightly open for a
few additional minutes to allow sufficient drying. In
addition, you can also activate the drying function
by pressing button “ “ (also see Section 3.5).
After the objects have dried, you can remove them
from the steam sterilizer and switch off the heating
by pressing button “ “.
Warning: The sterilization compartment, the door,
and the sterilized objects are very hot. You must
use the MELAG Tray Handle to remove the ob-
jects, or you must wear heat-protection gloves
during this operation.
3.3 Checking to ensure that the cycle has properly run ________________________
If there is no error message on the display at the end
of the program, and if the non-return pointer is be-
tween 1 and 1.3 bar for Program 1 (121°C) or be-
tween 2 and 2.4 bar for Program 2 (134°C), then the
program cycle has correctly run.

MELAtronic®
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3.4 Aborting the program _________________________________________________
You can abort (terminate) the program at any time.
Proceed as follows:
1. Push both of the following buttons, below the dis-
play, at the same time: the button to turn the drying
function off (10), and the time button (Show re-
maining run time, button [11]). The following error
message will appear on the display: “Err2”. At the
same time, the quick pressure release procedure
will automatically take place.
2. Observe the pressure gauge until the pressure
falls to “0”.
3. Acknowledge the error message by pressing the
time button (11).
4. You can now open the steam sterilizer door.
3.5 Removal of dry objects ready to use _____________________________________
Observe the following steps to ensure obtaining dry,
sterilized objects ready to use from the steam steri-
lizer:
1. Wait until the quick pressure release has auto-
matically taken place, and the reading on the
pressure gauge has fallen to “0”.
2. Open the door of the steam sterilizer slightly and
leave it ajar.
3. Press the button “ “ to turn on the drying func-
tion. The display will now show “Dry”, alternating
with the interior temperature of the sterilization
chamber.
4. Wait until the sterilized objects are as dry as you
require.
5. End the drying function by pressing the
button “ “.
Filter paper
Experience has shown that optimal results are ob-
tained by placing a sheet of filter paper on the tray,
then the objects to be sterilized, then on top of the
objects a second sheet of paper.
Do not use gauze or other types of cellulose for
this purpose
Do not use saturated cellulose products or gauze in-
stead of filter paper as described above. The steam
of the steam sterilizer can dissolve substances in cel-
lulose and gauze that will deposit in the form of spots
on the sterilized objects.
3.6 Frequency of daily sterilization _________________________________________
You can use this steam sterilizer to sterilize up to ap-
prox. eight (8) cycles per day. This large number of
sterilization cycles is made possible by the MELAG
system, which evaporates and re-condenses only a
relatively small amount of distilled or demineralized
water per sterilization cycle.
Waiting period between sterilization cycles
When a sterilization cycle finishes, a waiting period of
at least fifteen (15) minutes must be observed be-
tween the end of the one program and the beginning
of the next.
4 Additional information on sterilization
4.1 Total operating time (sterilization cycle time)______________________________
Operating times:
•Program 1 (1 bar at 121°C): 40 … 45 min
•Program 2 ( 2 bar at 134°C): 25 ... 30 min
When you begin the program with the “Start” button
(5), the program will begin and run fully automatically.
The actual sterilization time itself will begin to run only
when the respectively required sterilization tempera-
ture has been reached. Since the air-removal time
and the heating-up time until reaching of the required
sterilization temperature will depend on the loading of
the steam sterilizer, and on the temperature of the
sterilization chamber when the cycle starts, the total
operating time is not fixed and will vary within the two
ranges given above.
Times included in the total operating time
The total operating time (i.e., the overall time, or cycle
time) includes the individual time sequences such as
heating-up time, ventilation time, temperature-rise
time and equilibration time, and the sterilization time.
Sterilization time consists of the kill time and the
safety-margin period.
Drying time and drying temperature
Drying time: as desired
Drying temperature:
•Mantle of sterilization chamber: approx. 120°C
•Interior of sterilization chamber: approx. 60°C
The mantle of the sterilization chamber is kept con-
stantly at 120°C during the drying period. When the
heating system is on, “Dry” will appear on the display,
alternating with the interior temperature of the sterili-
zation chamber. You can deactivate the drying func-
tion by pressing the button to turn it off (10).

12
4.2 Using distilled or demineralized water ___________________________________
Water quality requirements
For steam sterilization, it is necessary to use steam-
distilled water (aqua dest) or fully demineralized water
(aqua dem).
Please observe the following guideline data for the
quality of the water that you use; this data is in ac-
cordance with the CEN standard DIN EN 285:
Conductivity
≤
15
µS/cm*
)
Evaporation residue
≤
10
mg/l
Silicon and SiO
2
≤
1
mg/l
Iron
≤
0.2
mg/l
Cadmium
≤
0.005
mg/l
Lead
≤
0.05
mg/l
Heavy metals, except for
the above
≤
0.1
mg/l
Chlorides
≤
2
mg/l
Phosphates
≤
0.5
mg/l
pH value
5 ... 7
Water colour
Colourless, clear,
without residue
Hardness
≤
0.02
mmol/l
*)µS/cm = microsiemens per centimetre
For operation of the steam sterilizer, fully deminer-
alized water in accordance with VDE 510 is also
sufficient, if this water meets VDE regulations (i.e.,
conductivity after water treatment ≤10 µS/cm*); con-
ductivity upon use ≤30 µS/cm*; pH value as set forth
in DIN EN 285; evaporation residues similar to those
set forth in DIN EN 285).
Sources of water
Demineralized water is available on the commercial
market in accordance with VDE 510. The label of the
purchased container must specifically verify that the
water meets classification specifications as set forth
in VDE 510.
Poor water can damage the steam sterilizer
If poor-quality water is used, scale deposits (calcium
carbonate, CaCO3) in the steam lines, the valves, and
the vent nozzle can impair the functions of the steam
sterilizer.
Formation of spots
The extent of spots produced on sterilized instru-
ments will depend on the quality of the water used to
produce the steam. For steam sterilization, it is nec-
essary to use steam-distilled water (aqua dest) or fully
demineralized water (aqua dem).
4.2.1 Amount of water consumed
After each sterilization cycle, the water in the steam
sterilizer storage tank will be reduced by the amount
of steam that does not completely condense. The ex-
act amount of losses will depend on a number of cir-
cumstances:
Factor: time interval between sterilization cycles
Water consumption will depend on the time between
sterilization cycles. If the distilled or demineralized
water in the storage tanks remains warm as a result
of continuous sterilization, the steam emitted from the
sterilization chamber will not completely condense.
Part of this steam will escape from the storage tank.
Cooling coils
If a long time has passed since distilled or demineral-
ized water has been refilled, and if the water level in
the storage tank has dropped below the cooling coils,
the emitted steam will also not fully condense, and will
escape.
4.2.2 Refilling with fresh water
Wasted water in the storage tank
The water in the storage tank will become quickly dirty
if the instruments are not carefully cleaned before
each sterilization process. You must regularly check
the water in the storage tank for cleanliness. If the wa-
ter is dirty and murky, or if there is a surface film on
the water, or if there
is a coating on the bottom and walls of the tank, then
you must by all means replace the distilled or demin-
eralized water in the tank. If there are greasy deposits
in the tank, we recommend filling the storage tank
with warm water containing a grease cutter (the Ger-
man product Pril or an equivalent), and cleaning out
the tank with a bottle brush. Then rinse out with fresh
water (for water quality, see Section 4.2 above).

MELAtronic®
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4.2.3 Emptying the water storage tank
You can drain out dirty water from the storage tank by
opening the drain (16) for distilled water (turn to the
left), and allowing the dirty water to flow into a con-
tainer. First, attach the supplied drain hose to the
sleeve of the drain (16).
Close the drain by turning to the right, and fill the stor-
age tank up to the “MAX” level with approx. three (3)
litres of distilled or demineralized water.
5 Troubleshooting
The following instructions will help you to correct mi-
nor malfunctions. They will also help you to give an
exact description of more serious trouble to your spe-
cialist MELAG dealer, your MELAG depot, or the
MELAG Customer Service representative.
5.1 Trouble without an error report _________________________________________
5.1.1 No display
If you switch on the power to the steam sterilizer, and
if nothing appears in the display, then check the fol-
lowing:
1. Check to make sure that the power cable is
properly plugged into the power socket.
2. Check to see if there power at the socket.
3. Check the fuses at the rear of the steam sterilizer.
If they have blown, replace them. Warning:Be-
fore opening the fuse mounts, unplug the power
cable. Replace with the spare fuses on the rear
wall of the steam sterilizer
5.1.2 No pressure display / Low reading on the pressure gauge
If, after a sterilization cycle, the red non-return (slave)
pointer does not show at least the pressure required
for the selected program, and if there is no error mes-
sage on the display, then the pressure gauge or the
red pointer of the gauge are probably defective. If so,
the pressure gauge must be replaced.
If you replace the pressure gauge, and if the pressure
indication is still too low, then the trouble is in the tem-
perature-control system (temperature sensor / elec-
tronic controller).
5.1.3 High reading on the pressure gauge
The red non-return pointer jams (fails to move)
It is possible that the red non-return will jam (stick),
and will fail to move. This may be caused if the white
pointer will try to drag along the “jammed” red pointer,
and if the pressure is great enough to “knock away”
the red pointer. The red pointer will then not stand at
the maximum pressure reached in the sterilization,
but will remain at the point where the white pointer
has knocked it. This means that the red pointer will
show a pressure that the steam sterilizer has not
reached in its cycle (for example, 4.5 bar). In such a
case, you can check to see the actual pressure
achieved in the steam sterilizer by standing in front of
the steam sterilizer and watching the white pointer
during a sterilization cycle.
Insufficient ventilation
If the pressure gauge shows a pressure that is con-
siderably higher than 1.3 bar for Program 1, or higher
than 2.4 bar for Program 2, then you must check the
ventilation functions of the steam sterilizer. Check as
follows:
1. Check to see if the feed-water filter in the sterili-
zation chamber is dirty.
2. Check to see if the vent nozzle in the water stor-
age tank is stopped up.
3. Check to see if the solenoid valve for pressure
release opens during the ventilation phase.
If these checks show that the ventilation process is
OK, and if the pressure on the gauge is still too high,
then the pressure gauge or the electronic tempera-
ture-control is defective.

14
5.1.4 Poor drying
Cause: you have not loaded the steam sterilizer
correctly
Do not load the steam sterilizer with more items than
the maximum specified amount. Be sure to arrange
the items on the trays so that the condensation can
properly run off.
Cause: you have not left the door slightly open
To achieve good drying, you must leave the steam
sterilizer door slightly open at the end of sterilization.
Cause: too much water remains in the steriliza-
tion chamber
It is not possible to avoid leaving a small amount of
water in the sterilization chamber after the cycle.
When the steam sterilizer cools, the residual steam
(no longer under pressure) will condense on those
surfaces that cool off first: the door and the bottom of
the chamber. The water will then collect at the bottom
of the chamber. The following can cause excessive
water to collect:
•The filter of the sterilization chamber is dirty.
•The solenoid valve that controls the water feed
leaks.
Cause: leak in the solenoid valve for water feed
If the instruments are not properly cleaned before
sterilization, small particles of debris can cause the
solenoid valve for water feed to slightly leak. The
steam sterilizer may still be able to reach the required
pressure, but water may drip from the water tank into
the sterilization chamber after sterilization. The prob-
lem here is not actually too much residual water.
Check for a valve leak as follows: Take out the tray
rack and wipe completely dry the inside of the sterili-
zation chamber. After a few hours, the chamber
should still be completely dry. If the chamber is wet,
clean out the solenoid valve by blowing it with air.
5.1.5 Overheating
Overheating is almost always caused by too little wa-
ter in the sterilization chamber. If the steam sterilizer
overheats:
•Switch off the steam sterilizer
•Open the door and allow the steam sterilizer to
cool down for 30 min
Before putting the steam sterilizer back into opera-
tion, check for the following possible causes:
Loading
When textiles are sterilized, they absorb a great
amount of steam and water. For this reason, never
put more textiles in the steam sterilizer than allowed.
Never operate the steam sterilizer without the tray
rack.
Vent nozzle
If instruments are not properly cleaned before sterili-
zation, particles of debris will enter the distilled or de-
mineralized water and, in turn, the steam. If the
steam sterilizer is then used frequently for long peri-
ods of time, these particles together with the long and
intensive action of the debris in the flowing air and
steam will cause the vent nozzle to “wash out”. This
means that the vent opening will be enlarged, and
that excessive steam will be lost. In such a case, the
vent nozzle must be exchanged.
Solenoid valves
If the instruments are not properly cleaned prior to
sterilization, debris will enter the solenoid valves for
water feed and for quick pressure release, and will
cause them to leak.
Safety valve
The safety valve is located in the water storage tank,
below the upper part of the U-shaped bow of the
“MAX” water-level mark. If this safety valve trips at
pressure-gauge readings of less than 2.5 bar of
steam, then it must be replaced.
5.2 Malfunctions with error messages_______________________________________
If any of the following error messages appear, you
must first acknowledge the message by pressing the
button to show remaining run time / cancel error mes-
sage (11), located below the display. After the cause
of the error has been eliminated (operator fault or
technical defect), then you must start the program
again like described under 3.2.

MELAtronic®
23
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5.2.1 The error message “Err1”
This error message means that the monitored time for
the heating-up phase has exceeded its limit. Check
for one of the following possible causes if “Err1” ap-
pears:
Too many items have been loaded
Make sure by all means that you do not load more
than the maximum amount allowed in these instruc-
tions.
Water-feed switch was not activated
The water feed switch was not activated, or it was not
switched off after a sufficient amount of water has en-
tered the sterilization chamber.
The door is not tightly sealed
Close the door tightly. If necessary replace the door
seal (gasket).
The vent nozzle is “washed out”
If the orifice of the vent nozzle has become washed
out, it will be too large for the steam sterilizer to reach
the required pressure. In such a case, replace the
nozzle.
Leaks in the valves
The solenoid valves for water feed and for quick pres-
sure release may be clogged and leaky. The pres-
sure-release valve may also have a leak.
The overheating protection function has tripped
Check the position of the jacket heating unit. This unit
should be pushed as far in as it can go at the bottom
rear fitting of the sterilization chamber.
The heating system is defective
An electrical check of the heating system is neces-
sary.
5.2.2 The error message “Err2”
You have aborted the running program
The error message “Err2” will appear after a program
has been started, and if the user then presses the but-
ton to turn the drying function off (10 and the button
for program selection (4).
Program selection
The error message “Err2” will appear if you start one
program, and then use the switch for program selec-
tion (4) to choose another program.
The power has failed
The error message “Err2” will appear if you start a
program, and if the power to the steam sterilizer fails
(i.e., if the building power fails, or if you switch off the
steam sterilizer by its power switch).
Temperature leaves required range
The error message “Err2” will appear if the actual tem-
perature has left the range required for the selected
program (temperature too high or too low).
5.2.3 Error message “1999”
This message will appear if the temperature sensor is
defective (the cable has broken, or there is a
short circuit).
6 Annex / Spare parts
6.1 Spare parts__________________________________________________________
Article no. Description of article
16005
Safety valve (officially calibrated)
34150 Door gasket for MELAtronic 23
34010
Filter for sterilization chamber
34125
Flow nozzle
35496
Temperature sensor for steam
34165
Pressure gauge
58740
Overheating protection unit (installed on the sterilization chamber)

16