EN/
0915/WLA Compact
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Hydraulic circuit
Water filter on chiller return:
if available, check its cleanliness and wash it with water, if required.
Hydraulic circuit seal:
check the presence of leaks and the seal of the fittings
Liquid to be cooled:
top up if the level of liquid is low. Switch the unit off and follow the instructions provided in
paragraph 7.4.
The added liquid must have the same quality and glycol composition of that poured in the circuit.
If required,the hydraulic circuit of the evaporator must be cleaned chemically (special maintenance).
Flow switch:
if available, check the intervention by simulating the lack of flow rate in the hydraulic circuit.
Electric circuit
Check the presence of motor current consumption anomalies.
Mechanical components
Clean inside the unit with a vacuum cleaner. Clean the pipes to facilitate the identification of leaks.
Check the presence of loose hardware that cause noise and vibrations.
9.3. Special maintenance
For information and quotations, contact the manufacturer technical support service (see "Contacts" at the end of
this paragraph).
Special maintenance operations include:
•
repair or replacement of any unit component activated with electric motor;
•
any intervention on the refrigerant circuit that requires the charge to be restored, e.g. repair or replacement of
components, such as dehydrator filter, thermostatic valve, evaporator, condenser, and compressor.
Refrigerant refill
Every time a leak is detected or the refrigerant circuit must be opened to replace a components, refill the refrigerant
circuit.
Perform the following operations if a leak is detected or if the circuit must be opened to replace a component.
1.
Collect the refrigerant in a collection device with pressure lower than 1 bar-a.
2.
Connect a vacuum pump via pressure gauge to the high and low pressure side.
3.
Remove the refrigerant from the vacuum pump (not from the compressor!) up to about 0 bar-a.
4.
Dispose of the refrigerant according to national standards.
5.
Fill the circuit with nitrogen at 1 bar-a.
6.
Repair the leak.
7.
Eliminate the humidity from the circuit with at least 3 filling and nitrogen extractions. When required, replace
the dehydrator filter.
8.
Once the circuit is closed, make sure to create the vacuum with a specific pump for a sufficient period of time.
On this purpose, check that the absolute pressure has reached at least 0.1 bar-a with the pressure gauge.
Make sure that upon switching the vacuum pump off, this pressure does not increase (its increase may
indicate that the welding has not been made correctly)
9.
Refill with R134a liquid using the compressor intake connection. The amount of refrigerant to be refilled is
equal to that indicated on the chiller data plate.
To prevent the compressor from suctioning great amounts of liquid, we recommend opening the
chiller cylinder valve for 10 s, close it and wait 1 minute before opening it again.
Compressor oil top up
For replacement or top up operations, use the top up inlet on the compressor, which consists of a Schrader valve.
The type of oil to be used must have equal characteristics to those indicated on the compressor data
place or contact the Service.
