Sanden GAUS-315EQTD Installation Manual page 18

Thermistor detection error
E045 HP defrost thermistor detection error
E047 High pressure side error
High ambient temperature defrost
E048
drive error
E070 Fan motor locked
E071 Fan motor revolution error
E073 Water circulation pump locked
E090
～
System control error
E150
Notes:
1. After a component is replaced or the inspection is completed, turn the unit on/off
several times to confirm the error does not re occur.
2. If the corrective actions above do not solve the error problem, a malfunction of the
PCB is highly likely.
Sanden Heat Pump – Installation Manual
Page 18 of 26
- Reconnect the expansion valve
connector, check if it is off the PCB
- Replace the expansion valve (together
with PCB), or the entire unit of heat
pump
- Check if the thermistor is mounted in
position on the evaporator
- Replace the defrost thermistor
- Check the heat pump piping filter for
any blockage
- Check if any piping bend, blocking or
crush
- Inspect if the pipes are being frozen
- Open the valve on water mains
- Open the stop valves
- If the water circulation pump is not
moving, replace the pump
- Remove foreign objects from the
evaporator (e.g. fallen leaves, grass,
snow)
- Replace the ambient temperature
thermistor
- Replace the defrost thermistor
- Reconnect the connector, check if it is
off the PCB
- Replace the fan motor
- Check for heat pump piping block and
crush
- Confirm that the connector on the
water circulation pump cable sitting on
the PCB properly
- Replace the water circulation pump
Replace the PCB