Mitsubishi Electric MXZ-2C20NA2-U1, Service Manual

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93
The other cases
Indoor unit does not operate. (different operating models in multi system)
• When you try to run 2 indoor units simultaneously, one for cooling and the other for heating, the unit which transmits signal to
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• When the above situation occurs, set all the indoor units to the same mode, turn OFF the indoor units, and then turn them
back ON.
• Though the top of the indoor unit sometimes gets warm, this does not mean malfunction. The reason is that the refrigerant gas
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•Check the voltage of power supply.
•
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recall function. (Refer to 11-2.2.)
Blink 5 times
&RQ¿UP
LED1 indication lamp on the
outdoor control P.C. board.
Replace the outdoor power
P.C. board.
Blink 9 times
Replace the outdoor control
P.C. board.
Turn OFF power supply before removing P.C. board.
&RQ¿UP
LED1 indication lamp
on the outdoor control P.C.
board.
Turn ON power supply. Start
operation.
Lighting
Replace the outdoor control
P.C. board.
Blink 9 times
Replace the outdoor power
P.C. board.
&RQ¿UP
LED1 indication lamp
on the outdoor control P.C.
board.
Turn ON power supply. Start
operation.
Normal
Lighting Lighting
&36
Infinity
Ÿ
No
Yes
1. Disconnect the connector CN63H in the outdoor control P.C. board.
2. Check the resistance of HPS after 1 minute has passed since the outdoor unit power supply was turned OFF.
Check the resistance between each terminal.
Reconnect CN63H.
Turn ON the power supply to the indoor and outdoor unit.
3 minutes later, start EMERGENCY OPERATION.
Is HPS protection displayed immediately
after compressor starts?
Replace HPS.
Replace the outdoor control P.C. board.
Normal
CN63H
Outdoor control
P.C. board
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