Mitsubishi Electric PRH-P8MYA Technical & Service Manual page 62

4) Emergency operation method
Piping work complete?
Check that mains power is OFF
Turn on emergency operation switch
(SWE) on indoor-side controller board
Short CN31
connector) on outdoor-side controller board
Set operation mode (cooling or heating) with SW4-2 on outdoor-side
board (SW4-1 not used)
Cooling
Turn on mains power
Check that emergency operation starts,
and that operation mode display flashes
5)
Emergency operation release method
a)
Turn off mains power.
b)
Turn off emergency operation switch
(SWE) on indoor-side controller board
c) Open CN31 (emergency operation
connector) on outdoor-side controller board
d)
Set SW4-2 as shown below
e)
Turn on mains power
Start
YES
(emergency operation
SW4
OFF ON
1
2
Heating
SW4
OFF ON
1
2
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* Before starting, recheck that the trouble allows
emergency operation.
✻1: For each refrigerant circuit
NO