Heat Controller VMH12SC-1, VMH24SC-1, VMH09SC-1 Indoor Unit Error Display, Diagnosis and Solution

Service Manual VMH Series Heat Controller, Inc.

9.1 Indoor Unit Error Display

Display	LED STATUS
E0	EEPROM parameter error
E1	Indoor / outdoor units communication protection
E2	Zero-crossing signal error
E3	Indoor fan speed out of control
E5	Open or short circuit of outdoor temperature sensor
E6	Open or short circuit of room or evaporator temperature sensor
E7	Outdoor fan speed out of control
P0	IBM malfunction or IGBT over-strong current protection
P1	Over voltage or too low voltage protection
P2	Temperature protection of compressor top.
P3	1 outdoor temp below 5°F(-15°C)
P4	Inverter compressor drive error

Note: E4 & P3: Reserved function

9.2 Diagnosis and Solution

EO:

9.2.1 EEPROM parameter error diagnosis and solution

Shut off the power supply and turn it on 5s later

Does EO code clear

Is the EEPROM chip plugged in indoor PCB well?

No

Correct the connection

Replace the main PCB of indoor unit

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