Heat Pump Manual
45
TROUBLE SHOOTING
On all units, circuit 1
– or CCT1 on the controller – is on the left hand side of the unit.
Other faults that are shown on the controller are
FLOW FAULT/ PUMP FAIL
The flow switch has open detecting a problem with the water flow. Some possible faults are
·
heat exchanger may be blocking up
·
faulty pump
·
faulty flow switch
·
technician isolated heat pump
·
On water to water units the flow fault could be hot or cold water
– the 2 flow sensors
are wired into the same circuit therefore both systems will need to be investigated. If
the evaporator water is the fault then the data log will show a gradual decline in water
flow. If it is the condenser water then the flow rate will cut off suddenly. If the
evaporator water has a problem then the pump needs to be looked at, there may be
debris blocking the heat exchanger or ice maybe forming. Ice will clear and the unit
will resume normal function however a good sign would be that there is a
contaminant forming is that the unit will not come back on line
Check
Unit Not Running
·
Power may be out or a phase may have dropped out
– check the phase rotation
relay
·
Low voltage
– check power is between 380 and 415V
·
Faulty controller
– check that the screen is active or the lights are on at the rear of
the controller
– if the screen develops a fault then the controller may still operate
·
Switching gear may be faulty
– check contactors are energising
·
Check for loose wiring
– the units vibrate during operation and can cause wiring to
come loose
If a trip occurs in the fault circuit the software will try and restart the unit or in the case of
multiple compressor unit it will try and restart the compressor that has faulted. It will do this
after twice the compressor hold times has elapsed
– default 4 minutes. If the system trips
again then the software try again to start the unit or compressor after another 4 minutes. If it
trips a third time in an hour then the controller will lock the unit out in a fault state. If the hour
lapses and the system has not tripped a third time then the count resets.
·
Check pump is running
·
check power to pump is OK,
·
check that unit is not isolated and all gate valves are open
·
Check that plate pack is not blocking up.
·
If plate pack blocked then replace plate pack
·
Check the controller is enabling the pump
– again the small green light next to the
correct output should be lit
