Periodical Maintenance; Service Operations To Be Carried Out By Qualified Technicians Or By The Manufacturer; Troubleshooting - Zanotti DBO 235 Use And Maintenance Instructions

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:

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.
4. Unsatisfactory efficiency of the unit
If the unit does not perform adequately and no defects can be identified, check that: cold room doors are
perfectly tight; no cold dispersion is available; the cold room is used wisely; no unfrozen liquids or foodstuffs are
placed in the low temperature room; the evaporator is ice-free.
We advise to install the units far from the doors, especially when the cold room is expected to be opened many
times a day.
WARNING:
Removal of protections during machine operation is absolutely forbidden. They have
been developed to safeguard the operator's safety.
5. Other troubles may be due to the triggering of the following electrical safety devices:
a) Fan thermal protection (incorporated in the motor) - automatic reset
It protects electric fans against high power absorption due to:
- overheating
• 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.
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