5-Maintenance and Service
2. Look over and clear the failure according to below information.
Failure
Possible causes for the failure
Solutions
Heat pump
cannot
be started
1 Wrong power supply
2 power supply cable loose
3 circuit breaker open
1 shut off the power and check power supply;
2 check power cable and make right connection
3 check for the cause and replace the fuse or
circuit breaker
Water pump is
running with
high noise or
without water
1 lack of water in the piping
2 much air in the water loop
3 water vavles closed
4 dirt and block on the water filter
1 check the water supply and charge water
to the piping;
2 discharge the air in the water loop;
3 open the valves in water loop;
4 clean the water filter.
Heat pump
capacity is low,
compressor
do not stop
1 lack of refrigerant;
2 bad insulation on water pipe;
3 low heat exchange rate on air side
exchanger;
4 lack of water flow
1 check for the gas leakage and recharge the
refrigerant;
2 make good insulation on water pipe;
3 clean the air side heat exchanger;
4 clean the water filter
High compressor
exhaust
1 too much refrigerant
2 low heat exchange rate on air side
exchanger
1 discharge the redundant gas
2 clean the air side heat exchanger
Low pressure
problem
of the system
1 lack of gas
2 block on filter or capillary
3 lack of water flow
1 check the gas leakage and recharge freon;
2 replace filter or capillary;
3 clean the water filter and discharge the air in
water loop.
Compressor do
not run
1 power supply failure
2 compressor contactor broken
3 power cable loose
4 protection on compressor
5 wrong setting on return water temp.
6 lack of water flow
1 check off the power supply;
2 replace compressor contactor;
3 tighten the power cable;
4 check the compressor exhaust temp.;
5 reset the return water temp.;
6 clean the water filter and discharge the air in
water loop.
High noise of
compressor
1 liquid refrigerant goes into
compressor
2 compressor failure
1 bad evaporation, check the cause for bad
evaporation and get rid of this;
2 use new compressor;
Fan do not run
1 failure on fan relay
2 fan motor broken
1 replace the fan relay;
2 replace fan motor.
The compressor
runs but heat
pump has not
heating or
cooling capacity
1 no gas in the heat pump;
2 heat exchanger broken;
3 compressor failure.
1 check system leakage and recharge
refrigerant;
2 find out the cause and replace the heat
exchanger;
3 replace compressor.
Low outlet
water
temperature
1 low water flow rate;
2 low setting for the desired water
temp.;
1 clean the water filter and discharge the air in
water loop.
2 reset the desired water temperature.
Low water flow
protection
1 lack of water in the system;
2 failure on flow switch
1 clean the water filter and discharge the air in
water loop.
2 replace the flow switch.
16
6-Excursus
Excursus1 The unit's parameter
Please set according the below table:
Par
Description
Limits
Unit
R01
R02
R03
R04
12
2
40
2
℃
℃
℃
℃
Cooling set-point
Cooling differential
Heating set-point
Heating differential
17
