LCX
RG66010687_rev.00
34
10.2 GENERAL
INFORMATION
It is a good idea to carry out periodic checks to ensure that the unit is working properly:
Check the efficiency of all the control and safety devices as previously described.
Check the terminals on the electric control board and compressor terminal boards to ensure that they
are securely tightened. The movable and fixed contacts of the circuit breakers must be periodically
cleaned and replaced whenever they show signs of deterioration.
Check the refrigerant level by means of the liquid level indicator (every 6 months).
Check the oil levels through the windows provided on the compressor crankcases (every 6 months).
Check the water circuit for leaks (every 6 months).
If the unit needs to be taken out of service for long periods of time, remove the water from the pipes
and the heat exchanger, from the pump/s (optional), the buffer tank (optional) and from the water coil
in the case of FREE-COOLING units (if no glycol solutions are used). This operation is essential if
during the time the unit is out of service ambient temperatures below the freezing point of the liquid
used are expected (typical seasonal operation).
Check the filling of the water circuit, bleeding air from the circuit through the valves situated in the
highest points.
Check the efficiency of the flow switch or differential pressure switch
Check the heating elements, where present, of the compressor crankcases.
Clean the metal mesh filters mounted externally on the water pipes.
Check the humidity indicator on the liquid level indicator (green = dry, yellow = humid); if the indicator
is not green as shown on the indicator sticker, replace the filter (every 6 months).
Check that the noise emissions of the unit are regular (every 6 months) and more specifically that no
vibrations and/or knocking can be detected.
10.3 REPAIRING THE COOLING CIRCUIT
Attention: while performing repairs on the cooling circuit or maintenance work on
the compressors, make sure the circuit is left open for as little time as possible.
Even if briefly exposed to air, ester oils tend to absorb large amounts of humidity,
which results in the formation of weak acids.
If the cooling circuit has undergone any repairs, the following operations must be carried out:
-
tightness
test;
-
emptying and drying of the cooling circuit;
-
loading with refrigerant.
If the system has to be drained, always recover the refrigerant present in the circuit using
suitable equipment; the refrigerant should be handled exclusively in the liquid phase.
10.4 TIGHTNESS
TEST
Fill the circuit with anhydrous nitrogen supplied from a tank with a pressure reducer until the pressure
rises to 10 bars.
During the pressurisation phase, do not exceed the pressure setting of the safety valves;
otherwise you will cause the latter to open.
The presence of any leaks must be determined using special leak detectors. Should any leaks be
detected during the test, empty out the circuit before repairing the leaks with suitable alloys.