12. ROUTINE MAINTENANCE
Good operation of the unit requires the condenser to be cleaned periodically (frequency of cleaning depends on
the environment where the unit is installed).
Turn off the unit and clean it by blowing air from the inside outwards. Should no air jet be available, use a long-
haired brush and work on the outside of the condenser.
In case of water-cooled condensers have the unit cleaned by a plumber with special descaling agents.
WARNING
Use safety gloves to protect your hands from possible cuts.
WARNING
Disconnect the unit before w orking on it.
12.1 Periodical maintenance
Periodically check wear condition of electrical contacts and remote switches; if necessary replace them.
12.2 Service operations to be carried out by qualified technicians or by the manufacturer
Following operations shall be carried out by qualified technicians or by the manufacturer exclusively. Under no
circumstances the user is allowed to:
replace electrical components
work on the electric equipment
repair mechanical parts
work on the refrigerating system
work on the control panel, ON/OFF and emergency switches
work on protection and safety devices
12.3 Troubleshooting
During operation following troubles may occur:
1. Compressor stops. The unit is equipped with an overtemperature device which stops the compressor every
time the max. allowable temperature of motor windings is exceeded. Possible causes are:
- insufficient ventilation of the room where the unit is installed.
- anomaly in mains voltage.
- faulty operation of condenser fan.
- Device reset is automatic.
2. Ice forms on the evaporator preventing air from flowing regularly.
Possible causes are:
- the door is opened too frequently;
- faulty operation of evaporator fan;
- faulty solenoid valve (in models with hot gas defrost);
- faulty defrost heater (in models with electric defrost);
- faulty defrost process. In this case some measures can be taken:
increase defrost termination temperature by some degrees, increase number of defrosts.
ATTENTION
Do not use either hot w ater or any pointed, cutting, metal objects to remove ice
blocks.
3. Display does not light up. Check:
- if there is power to the unit;
- if mains cable is connected properly;
- fuses inside the electric panel
4. Unit does not start operating when pressing ON/OFF key (the display is turned on): check microdoor
connection keeping in mind that the switch contact must be closed when the door is closed.
Unsatisfactory efficiency of the unit:
If no defects are found in the unit check that: cold room doors are perfectly tight; there is no cold dispersion;
the cold room is used wisely; no unfrozen liquids or foodstuffs are placed in the low temperature room; the
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