Unit installation

Use and Maintenance Manual Air-cooled water chillers and Heat Pumps R-PAE/R-PAH/EAH Rev. 1 del 03/09

TROUBLE POSSIBLE CAUSE CORRECTIVE ACTION

A) Automatic switch activated

Reset the automatic switch; check the cause

for the activation

11. The compressor does

not work

B) Compressor internal heat protection

activated

Check the compressor winding resistance

; after

reset, check the tension and the electric absorption;

check the working parameters are in the nominal

range of values

C) The contactor does not work Check the contacts and the contactor coil

Check the thermostatic valve overheating is correct;

12. The compressor is noisy

A) Liquid return to the compressor check the valve bulb is properly placed, fixed and

insulated

B) The compressor is damaged Replace the compressor

13. Probe alarm

A) The probe corresponding to the alarm

code is defective or disconnected

Check the probe connection and if it works; in case of

defect, replace it.

5.6 Routine maintenance

5.6.1 Type and frequency of periodical checks

Before acceding any component inside the unit, turn the main switch of the power supply to OFF position.

Then, also turn the unit main switch to OFF position.

Only trained technicians are alllowed to perform operations with powered electrical panel and with

open panel board, since some functions of the system fail.

It is recommended to carry out periodical checks in order to make sure the unit works properly. Only authorized and

skilled technicians are allowed to perform this kind of operations, included any maintenance operation.

5.6.2 Operations on the cooling circuit

Every time an operation involves the cooling circuit discharge, the gas must be collected by means of the appropriate

gas recovery for environmental safety reasons.

Once the repair on the cooling circuit is performed, carry out the following operations:

Leak detection;

Vacuum and dehydratation;

Refrigerant charge.

A) LEAK DETECTION

Charge the cooling circuit with the gasous refrigerant up to reach a pressure of 1 bar. Then, add anhydrous nitrogen by

means of cylinders with reducer up to reach a pressure of 15 bar.

Look for possible leakage and, if present, discharge the cooling circuit before welding (with phosphorus copper

alloy with a minimum of 2% of silver).

Discharge completely the cooling circuit before welding in order to avoid explosions.

Do not use oxigen instead of nitrogen in order to avoid explosions.