II.15 Troubleshooting
Problem
1 – THE CIRCULATION PUMP DOES NOT START (IF CONNECTED): water differential pressure switch alarm
Lack of voltage to the pump unit:
No signal from control board:
Pump blocked:
Pump motor malfunction:
The water mesh filter (mounted by installed) is dirty:
2 - COMPRESSOR: DOES NOT START
Microprocessor board alarm:
Absence of voltage, isolator switch open:
Circuit breakers tripped due to overload:
No request for cooling with user system set point correct:
Absence of heating demand in user with correct set working set:
Working set point too high in cooling mode:
Setting the working set too high in heating mode:
Defective contactors:
Compressor electric motor failure:
Head of the compressor very hot, internal circuit breaker tripped
3 - THE COMPRESSOR DOES NOT START BUT A BUZZ IS TO BE HEARD
Incorrect supply voltage
Defective contactors:
Mechanical problems in the compressor:
4 – THE COMPRESSOR RUNS INTERMITTENTLY:low pressure alarm from the transducer
Faulty low pressure transducer:
Insufficient refrigerant charge.
Refrigerant line filter clogged (appears frosted):
clean the filter body and replace cartridge.
5 - THE COMPRESSOR STOPS: high pressure switch alarm
Faulty high pressure switch:
Insufficient cooling air to the batteries (in cooling mode):
Insufficient water circulation on the plate exchanger (in heating mode):
Excessive ambient temperature:
Presence of air in the water system:
Excessive refrigerant charge:
6 - EXCESSIVE COMPRESSOR NOISE - EXCESSIVE VIBRATIONS
The compressor is pumping liquid, excessive increase of refrigerant fluid in the crankcase.
Mechanical problems in the compressor:
Unit running at the limit of specified conditions of use:
7 - COMPRESSOR ACCORDING TO STATED
Excessive thermal load.
Working set point too low in cooling mode:
Setting the working set too high in heating mode:
Poor ventilation of the coils:
Bad water circulation in the plate exchanger:
Presence of air in the chilled water system:
Insufficient refrigerant charge.
Refrigerant line filter clogged (appears frosted):
Control board faulty:
clean the filter body and replace cartridge.
Irregular working of the contactors:
8 - LOW OIL LEVEL
Leak in the refrigerant circuit:
Unit running under irregular conditions compared to the functioning limits:
9 - THE CRANKCASE RESISTANCE DOES NOT WORK (WITH COMPRESSOR OFF)
Lack of electrical power supply:
The crankcase resistance is off:
10 - HIGH DELIVERY PRESSURE TO NOMINAL CONDITIONS
Insufficient cooling air to the batteries (in cooling mode):
Insufficient water circulation on the plate exchanger (in heating mode):
Presence of air in the water system:
Excessive refrigerant charge:
Dirty or blocked batteries (in cooling mode):
EQPI3X
Recommended action
check electrical connections.
check, call in authorised service engineer.
check and clear as necessary.
overhaul or replace pump.
clean the filter.
identify alarm and take appropriate action.
close isolator switch.
restore the switches; check the unit at start-up.
check and if necessary wait for a cooling request.
check and if necessary wait for heating request.
check and if necessary readjust set-point.
check and if necessary readjust set-point.
replace contactor.
check the short circuit.
Wait an hour at least for cooling
check voltage, investigate causes.
replace contactor.
replace compressor.
check operation of pressure switch.
1 Detect and eliminate any leaks;
2 restore correct load.
replace filter.
check its operation and replace if necessary.
check operation of pressure switch.
check fans, check clearances around unit and possible coil obstructions.
check and adjust as necessary.
check unit functioning limits.
bleed the water system.
drain the excess.
1 check operation of the expansion valve;
2 check superheating;
3 replace expansion valve if necessary.
overhaul compressor.
check performance according to declared limits.
check system sizing, leakage and insulation of rooms served.
check calibration and reset.
check calibration and reset.
check fans, check clearances around unit and possible coil obstructions.
check and adjust as necessary.
bleed the system.
1 Detect and eliminate any leaks;
2 restore correct load.
replace filter.
replace the board and check.
check its operation and replace if necessary.
check functioning.
1 check, identify and eliminate any leaks.
2 restore correct load of refrigerant and oil.
verify sizing of the unit.
check connections
check and replace if necessary.
check the function of the fans, the respect of the technical spaces and possible obstructions to the
batteries.
check and adjust as necessary.
bleed the system.
drain the excess.
verify and eventually clean and / or remove obstructions.
EN
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