Troubleshooting - Hitecsa EQRU2160 Installationsanleitung

2.12. TROUBLESHOOTING

Problem
1 – THE CIRCULATION PUMP DOES NOT START (IF CONNECTED): water differential pressure switch alarm
No voltage to the pump unit
No signal from control board
Pump blocked
Pump motor failure
The water mesh filter (mounted by installer) is dirty
2 - COMPRESSOR: IT DOES NOT START
Microprocessor board alarm
No voltage, switch open
Circuit breakers tripped due to overload
No request for cooling on user with correctly entered work set-point
No request for heating on user with correctly entered work set-point
Work set-point too high in cooling mode
Work set-point 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 YOU CAN HEAR A BUZZING NOISE
Incorrect supply voltage
Defective contactors
Mechanical problems in the compressor
4 - THE COMPRESSOR WORKS INTERMITTENTLY: low pressure pressure-switch alarm
Faulty low pressure transducer
Insufficient amount of refrigerant fluid
Clogged refrigerant fluid line filter (appears frosted)
Irregular operation of the expansion valve
5 - THE COMPRESSOR STOPS: high pressure pressure-switch alarm
Faulty high pressure switch
Not enough cooling air in coils (in cooling mode)
Not enough water circulation on the plate heat exchanger (in heating
mode)
High ambient temperature
Presence of air in the water system
Excessive amount of refrigerant fluid
6 - Excessive compressor noise - Excessive vibrations
The compressor is pumping liquid, excessive refrigerant fluid in crankcase
Mechanical problems in the compressor
Unit running at the limit of the specified condition of use
7 - Compressor runs continuously
Excessive thermal load
Work set-point too low in cooling mode
Work set-point too high in heating mode
Poor ventilation in the coils
Poor water circulation in the plate exchanger
Presence of air in the chilled water system
Insufficient amount of refrigerant fluid
Clogged refrigerant fluid line filter (appears frosted)
Faulty control board
Irregular operation of the expansion valve
Irregular contactor operation
IOM_EQRU-SS_EQRHU-SS_2160a4350_208676_230601_ES-EN-FR-DE-IT
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Recommended action
check the electrical connections
check, call in authorised assistance
check and clear as necessary
repair or replace pump
clean the filter
identify alarm and take appropriate action
close the isolator
reset the switches; check the unit at start-up
check and if necessary wait for 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 the contactor
check for short circuit
wait an hour at least for cooling
check voltage, investigate causes
replace the contactor
replace the compressor
check operation of pressure switch
1. detect and eliminate any leaks
2. top-up to the correct amount
replace the filter
check calibration, adjust overheating, 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. 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. top-up to the correct amount
replace the filter
replace the board and verify
check calibration, adjust operation, replace if necessary
check operation
EQRU-EQRUSS
EQRHU-EQRHUSS