Starting; Wiring; Maintenance And Repairs; Routine Maintenance - Zanotti CU Serie Manual De Uso

9.1

Starting

To start the unit act as follows:
A) Pre-heating: always recommended for at least 4 hours. In case of particularly cold weather pre-heat for a
longer time (at least 12 hours). Pre-heating shall be carried out every time the unit does not work for over 24
hours.
When pre-heating, set the thermostat of the equipment connected with the condensing unit at a higher
temperature than the outside temperature.
B) Place the main switch in position (1) and let the unit in this state for the recommended time.
C) When the recommended time has elapsed, set the thermostat of the equipment connected with the condensing
unit at the desired temperature. In these conditions the unit will be enabled to start operation.
D) If the compressor does not start, check the following:
leak, repair it, refill the compressor and repeat above operations.
ATTENTION: FOR SCROLL COMPRESSORS
Make sure that compressor rotates in the right direction by checking suction and
condensation pressures (by means of the manometers applied on the unit). Should the
direction be wrong, STOP THE UNIT IMMEDIATELY to prevent the compressor from
being damaged. Turn off the unit, open the electric panel and exchange one of the two
phases. Repeat starting.
10.

Wiring

A wiring diagram, specific for the units of the CU 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

- if there is power in the unit;
- Minimum pressure switch cutout = no refrigerant available. In this case identify the
- Faulty auxiliary fuse = identify and eliminate the cause.
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