Troubleshooting - RHOSS TCCE 135 Gebrauchsanweisung

II.7

TROUBLESHOOTING

1 - THE PRIMARY CIRCULATION PUMP DOES NOT START (IF CONNECTED): water differential pressure switch alarm
No power to pumping assembly.
No signal from control board.
Pump jammed.
Pump motor malfunction.
Pump speed switch malfunction.
Working set point reached
2 – COMPRESSOR: WILL NOT RUN
Microprocessor board alarm.
No power supply, general isolator open.
Overload protection triggered.
No request for cooling (or heating in heat pump operating mode) from user with
correct working set point.
Working set point too high (too low in heat pump operating mode).
Faulty contactors.
Compressor electric motor malfunction.
3 – COMPRESSOR DOES NOT START: BUZZING NOISE HEARD
Incorrect power supply voltage.
Compressor contactor malfunction.
Mechanical problems in the compressor.
4 - THE COMPRESSOR STARTS AND STOPS: low pressure switch alarm
Low pressure switch malfunction.
Insufficient refrigerant charge.
Refrigerant line filter clogged (appears frosted).
Expansion valve malfunction.
5 - THE COMPRESSOR STOPS: high pressure switch alarm
High pressure switch malfunction.
Insufficient cooling air at the coils (during chiller function).
High ambient temperature.
Insufficient water circulation at the plate exchanger (during heat pump
function).
Air in the water system (during heat pump function).
Excessive refrigerant charge.
6 - COMPRESSORS TOO NOISY - EXCESSIVE VIBRATIONS
Compressor is pumping liquid, excessive refrigerant fluid in crankcase.
Mechanical problems in the compressor.
Unit running at the limit of the intended conditions of use.
7 - THE COMPRESSOR RUNS CONTINUOUSLY
Excessive thermal load.
Working set point too low in cooling cycle (too high in heating cycle).
Insufficient coil ventilation (during chiller function).
Insufficient water circulation at plate exchanger (during heat pump function).
Air in the water system (during heat pump function).
Insufficient refrigerant charge.
Refrigerant line filter clogged (appears frosted).
Control board malfunction.
Expansion valve malfunction.
Contactor malfunction.
8 - HIGH DELIVERY PRESSURE AT RATED CONDITIONS
Insufficient cooling air at the coils (during chiller function).
Insufficient water circulation at the plate exchanger (during heat pump
function).
Air in the water system (during heat pump function).
Excessive coolant charge.
Problem
SECTION II: INSTALLATION AND MAINTENANCE
Recommended action
Check electrical connections and auxiliary fuses.
Check, call an authorised service centre.
Check, unblock if necessary.
Repair or replace pump.
Check, replace component.
Check.
Identify alarm and intervene if necessary.
Close general isolator.
1 Reset switch.
2 Check unit at start up.
Check and if necessary wait for cooling (heating) request.
Check and if necessary reset calibration set point.
Replace or repair contactors
Check for short circuit.
Check voltage and correct phase sequence, verify cause.
Replace contactor.
Recondition the compressor.
Check pressure switch calibration and operation.
1 identify and eliminate any leaks;
2 restore correct charge.
Replace filter.
Check calibration, adjust overheating, replace if necessary.
Check pressure switch calibration and operation.
1 Check clearances and make sure coils are not obstructed.
2 Check fan function.
3 Check operation of the fan control panel for the versions CC, AP &
CC, LA, AP & LA.
Check unit working limits.
Check and adjust if necessary.
Bleed the water system.
Discharge excess.
1 Check expansion valve operation.
2 check superheating.
3 adjust superheating, if necessary replace expansion valve.
Recondition the compressor.
Check yields according to stated limits.
Check system sizing, leakage and insulation.
Check calibration and reset.
1 Check clearances and make sure coils are not obstructed.
2 check fan function.
Check and adjust if necessary.
Bleed the system.
1 identify and eliminate any leaks;
2 restore correct charge.
replace filter.
Replace board and check.
Check calibration, adjust operation, replace if necessary.
Check operation.
1 Check fan function, clearances and make sure there are no
obstructions in the coils.
2 Check operation of the fan control panel for the versions CC, AP &
CC, LA, AP & LA.
Check, adjust if necessary.
Bleed the system.
Discharge excess.
48