Baxi MK SYSTEM Installation, User And Service Manual page 76

13 Troubleshooting
Code Message
H06.28 Comm IDU - ODU
H06.29 ODU-interface
H06.30 ODU temperature
H06.31 ODU temp sensor
H06.32 ODU temp sensor
H06.33 ODU heatsink temp
H06.34 ODU power module
H06.35 ODU superheat
H06.36 Fan motor
76
Description
Communication error between the indoor unit and outdoor unit
Error code shown on the digital display of the outdoor unit: E2
The main PCB B and the main control PCB of the hydraulic module are not connec­
ted. Connect the wire.
Check the value of signal HM024. If the value of HM024 is less than 75%, the com­
munication errors are too severe. It is essential to use a shielded communication ca­
ble.
If there is a strong magnetic field or strong interference, (e.g. lifts, powerful trans­
formers), add a barrier to protect the unit or move the unit to another location.
1. Switch off the outdoor unit and the indoor unit.
2. Wait 3 minutes for the outdoor unit capacitors to discharge.
3. Switch on the indoor unit then the outdoor unit.
Mismatch between the outdoor unit and the interface board
The outdoor unit temperature is anomalous
Error code shown on the digital display of the outdoor unit: P4
The discharge temperature sensor connector is loose. Reconnect it.
The discharge temperature sensor connector is wet or contains water. Drain the wa­
ter, dry the connector and add waterproof adhesive.
The discharge temperature sensor is faulty. Replace it.
Outdoor unit temperature sensor error
Check the wiring between the main PCB and the sensors.
Check that the sensors have been fitted correctly.
Check the Ohmic value of the sensors.
Replace the sensors if necessary.
Outdoor unit temperature sensor error
Check the wiring between the main PCB and the sensors.
Check that the sensors have been fitted correctly.
Check the Ohmic value of the sensors.
Replace the sensors if necessary.
Outdoor unit heatsink temperature is anomalous
Heat sink = radiator
Error code shown on the digital display of the outdoor unit: C7
Outdoor unit power module is anomalous
Error code displayed on the outdoor unit digital display: bH, H4, P6, L0, L1, L2, L4, L5,
L7, L8, or L9
The power supply voltage of the unit is low, increase the power supply voltage to the
required range.
The space between the units is too narrow for heat exchange. Increase the space
between the units.
The heat exchanger is dirty or clogged. Clean the exchanger.
The fan is not running. The fan motor or the fan is broken. Replace it.
The refrigerant level is too high. Adjust the quantity of refrigerant.
The water flow rate is low, there is air in the system or the pump stroke is insuffi­
cient. Release the air and reselect the pump.
The water outlet temperature sensor is loose or broken, reconnect it or replace it.
The wires or screws on the module are loose. Reconnect the wires and tighten the
screws. The thermally conductive adhesive has dried out or has fallen off. Add a little
thermally conductive adhesive.
The wire connection is loose or has fallen off. Reconnect the wire.
The inverter module board is faulty, replace it.
If you find that there is no problem with the control system, then the compressor is
faulty, replace it with a new one.
The stop valves are closed, open them.
The outdoor unit superheat is anomalous
Outdoor unit fan motor is anomalous.
Error code shown on the digital display of the outdoor unit: H6, HE or HH
A strong wind is blowing against the fan, making it turn in the opposite direction. Re­
orient the unit or shelter it to prevent the wind from blowing against the fan.
The fan motor is broken, replace it.
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