emmeti EC 0510 Manuel D'installation Et D'utilisation page 47

II.11 CHECK-LIST
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.
Working set-point reached
2 - THE COMPRESSOR DOES NOT START
Microprocessor board alarm:
Absence of voltage, isolator switch open:
Automatic overload switches activated:
No request for cooling/heating with user system set point correct:
Working set-point set too high in cooling mode (too low in heating or heat
recovery mode):
Defective contactors:
Compressor electric motor failure:
Head of the compressor very hot, internal thermal protection activated
3 –THE COMPRESSOR DOES NOT START BUT YOU CAN HEAR A BUZZING NOISE
Incorrect power supply voltage:
Defective contactors:
Mechanical problems in the compressor:
4 – THE COMPRESSOR RUNS INTERMITTENTLY: low pressure switch alarm
Faulty low pressure switch:
Insufficient refrigerant charge.
Refrigerant line filter clogged (appears frosted):
Irregular operation of the expansion valve:
5 – THE COMPRESSOR STOPS: high pressure switch alarm
Faulty high pressure switch:
Insufficient cooling air in coils
(in cooling mode):
Excessive ambient temperature:
Insufficient water circulation on the plate exchanger
(in heating or heat recovery mode):
High water temperature (in heating or heat recovery mode)
Presence of air in the water system (in heating or heat recovery mode):
Excessive refrigerant charge.
6 – EXCESSIVE COMPRESSOR NOISE - EXCESSIVE VIBRATIONS
Compressor is pumping liquid, excessive increase in refrigerant fluid in
crankcase.
Mechanical problems in the compressor:
Unit running at the limit of specified conditions of use.
7 - COMPRESSOR RUNS CONTINUOUSLY
Excessive thermal load.
Working set-point set too low in cooling mode (too high in heating or heat
recovery mode):
Poor ventilation to the coils (in cooling mode):
Poor water circulation on the plate exchanger (in heating or heat recovery
mode):
Presence of air in the chilled/hot water system and/or heat recovery
system.
Insufficient refrigerant charge.
Refrigerant line filter clogged (appears frosted):
Control board faulty:
Irregular operation of the expansion valve:
Irregular working of the contactors:
Problem Recommended action
check electrical connections.
check, call in authorised service engineer.
check and clear as necessary.
repair or replace pump.
check
identify alarm and take appropriate action.
close isolator switch.
reset the switches; check unit on start-up.
check and if necessary wait for cooling/heating) request.
check and if necessary readjust set-point.
replace contactor.
check for short circuit.
Wait an hour at leat for cooling
check voltage, investigate causes.
replace contactor.
replace compressor
check operation of pressure switch.
1 identify and eliminate any leaks;
2 restore correct charge.
replace filter.
check calibration, adjust superheating, replace if necessary.
check operation of pressure switch.
check fans, check clearances around unit and possible coil obstructions.
check unit operating limits.
check and adjust if necessary.
check unit operating limits.
bleed the water system.
drain the excess.
1 check operation of the expansion valve.
2 adjust superheating.
3 replace the expansion valve if necessary.
overhaul compressor.
check capacities according to stated limits.
check the system dimensioning, leaks and insulation of the rooms
concerned.
check setting and reset.
check fans, check clearances around unit and possible coil obstructions.
check and adjust as necessary.
bleed the system.
1 identify and eliminate any leaks;
2 restore correct charge.
replace filter.
check by substitution.
check calibration, adjust, replace if necessary.
check operation.
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SECTION I: USER