Outdoor Unit Error; E2 (Odu) Communication Failure Between Indoor And Outdoor Unit; E4, E5, E6 (Odu) Temperature Sensor Fault; E9 (Odu) Ac Over-Voltage / Under-Voltage Protection - Omega OTEC IEWB Series Service Manual

 Faulty problem
Troubleshooting and repair:
a) Check if there is a short circuit in CN2 port.
b) Change a new PCB.

Outdoor unit error

2.4.8 E2 (ODU) Communication failure between indoor and outdoor unit

Same as 5.4.1

2.4.9 E4, E5, E6 (ODU) temperature sensor fault

Same as 5.4.2

2.4.10 E9 (ODU) AC over-voltage / under-voltage protection

Description: Abnormal increases or decreases in voltage are detected by checking the specified
voltage of detection circuit.
Possible reason:
 Power supply error
 Refrigerant system leakage or block
 Faulty outdoor unit PCB
Troubleshooting and repair:
a) Check the power supply and measure the voltage.
b) Repower on the unit and measure the voltage between P and N. When the unit is in standby, is the
voltage between P and N about 310VDC, 340VDC or 380VDC? When start up the unit, is it in
220V~400V? If not, replace a new outdoor PCB. If yes, go to next step.
c) Check the reactor.

2.4.11 E10 (ODU) Outdoor unit EEPROM error

Same as 5.4.4

2.4.12 E11 (ODU) Indoor unit fan motor fault

Please refer to 5.4.5

2.4.13 E12 (ODU) IPM temperature sensor fault

Description: the sampling voltage is not at 5V
Possible reason:
 Power supply error
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