10. WIRING
A wiring diagram, specific for the units of the DBO series, is enclosed with these use and maintenance
instructions.
11. MAINTENANCE AND REPAIRS
Suitable maintenance is crucial for obtaining longer life, perfect working conditions and high efficiency of the
unit as well as for ensuring the safety features provided by the manufacturer.
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 working 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 the following troubles may occur:
1. The unit does not operate perfectly.
Check the refrigerating gas on the specially-fitted indicator available on all units fitted with a thermostat
(check when the unit is operating and the cold room temperature is closed to the required value).
Normally the indicator is clear; in the absence of gas, gas bubbles will appear.
2. Compressor or fans have stopped working.
- Check fuses and circuit breakers protecting the main circuit. Should they have been activated, replace
fuses or restore circuit breakers making sure that supply voltage and phase polarity are correct.
- Check the circuit breaker protecting the auxiliary circuit or the fuse in the electronic control box.
- If motor fan stops working, it can be restarted automatically, but the cause of the trouble should be
identified. Check compressor/fan overtemperature devices inside the electric panel. Switch off mains
switch before operating on same.
3. Malfunctioning
- Check if the evaporator is ice-free; if necessary, immediately defrost the evaporator completely by
pressing key (8) for 8 seconds (manual defrost). Once the defrosting cycle is completed, check if any
ice has been left on the evaporator and repeat above operation.
Shorter timer intervals between defrosting cycles should be set to reduce ice formation.
ATTENTION:
Do not use either hot water or any pointed, cutting, metal objects to remove ice from the
evaporator.
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