II.11
SCHEMATIC TROUBLESHOOTING
Problem:
1 - THE CIRCULATION PUMP DOES NOT START (IF CONNECTED):
Lack of voltage to the pump unit:
No signal from the control board:
Pump blocked:
Faulty pump motor:
Faulty pump speed switch:
Work set-point is reached:
2 - THE COMPRESSOR DOES NOT START:
Microprocessor board alarm:
No voltage; manoeuvre isolator switch open:
Tripped compressor thermal protection:
Tripped overload fuses:
No request for cooling with working set point correct:
Work set-point too high:
Defective contactors:
Compressor electric motor failure:
3 - THE COMPRESSOR DOES NOT START - A BUZZING SOUND IS HEARD:
Incorrect power supply voltage
Faulty compressor contactors:
Mechanical problems in the compressor:
4 - THE COMPRESSOR WORKS INTERMITTENTLY:
Faulty low pressure switch:
Insufficient refrigerant:
Blocked gas line filter (appears frosted):
Irregular operation of the expansion valve:
5 - THE COMPRESSOR STOPS:
Malfunctioning high pressure switch:
Insufficient cooling air to the coils:
High ambient temperature:
Refrigerant charge excessive:
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 conditions of use:
7 - THE COMPRESSOR RUNS CONTINUOUSLY
Excessive thermal load:
Work set-point too low:
Poor ventilation in the coils:
Insufficient refrigerant:
Blocked filter (appears frosted):
Control board faulty:
Irregular operation of the expansion valve:
Irregular contactor operation:
8 - THE COMPRESSOR PARTIALISES CONTINUOUSLY
Work set-point too high:
Insufficient water flow:
9 - LOW OIL LEVEL
Refrigerant leakage:
Crankcase resistance interrupted:
Unit running is anomalous conditions:
SECTION II: INSTALLATION AND MAINTENANCE
Recommended action:
check the electrical connections and auxiliary fuses.
check, request authorised assistance.
check and clear as necessary.
repair or replace the pump.
repair or replace the component.
check.
identify the alarm.
close isolator.
check the electrical circuits and the motor windings and identify any short
circuits; check for an overload in the mains and any loose connections.
reset the fuses and check the unit at start-up.
check and if necessary, wait for the cooling request.
check setting and reset.
replace or repair.
check for a short circuit.
check voltage, investigate causes.
replace.
repair compressor.
check the calibration and functions.
top-up the correct amount, identify and eliminate any leaks.
replace.
verify its correct operation and if necessary, replace.
check the calibration and functions.
check fans, check clearances around unit and possible coil obstructions.
check unit operation limits.
drain the excess.
verify whether the expansion valve works correctly and if necessary,
replace it.
repair compressor.
verify compliance with the stipulated limits.
verify the system size, leaks and insulation.
check setting and reset.
check fans, check clearances around unit and possible coil obstructions.
top-up the correct amount, identify and eliminate any leaks.
replace.
replace the board and verify.
replace.
verify the functions.
check setting and reset.
check and adjust as necessary.
verify, identify and eliminate the leak; top-up the correct amount of
refrigerant and oil.
verify and replace, if necessary.
verify the unit sizing.
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