Mitsubishi Electric PUHY-P72 Service Manual page 113

[ VII Control ]
-13- Emergency Operation Mode
1. Problems with the outdoor unit
Emergency operation mode is a temporary operation mode in which the outdoor unit that is not in trouble operates when one
of the outdoor units in the P144 through P240 models is in trouble or when one or two of the outdoor units in the P264 througt
P360 models are in trouble.
This mode can be started by performing an error reset via the remote controller.
(1) Starting the emergency operation
1) When an error occurs, the error source and the error code will be displayed on the display on the remote controller.
2) The error is reset using the remote controller.
3) If an error code appears that permits an emergency operation in step 1) above, (See the table below.), the retry operation
starts.
4) If the same error is detected during the retry operation (step 3 above), an emergency operation can be started by resetting
the error via the remote controller.
Error codes that permit an emergency operation (Applicable to both OC and OS)
Trouble source
Compressor
Fan motor
Inverter
TH2
TH3
TH4
Thermistor
TH5
TH6
TH7
Power
Emergency operation pattern (2 outdoor units)
Emergency operation pattern (3 outdoor units)
OC
OS1
OS2
Cooling
Emergency
operation
Heating
Maximum total capacity
of indoor units (Note 1)
(Note 1) If an attempt is made to put into operation a group of indoor units whose total capacity exceeds the maximum allowable capacity,
some of the indoor units will go into the same condition as Thermo-OFF.
HWE0804A
Error codes that permit an
emergency operation
0403 Serial communication error
4220, 4225 Bus voltage drop
4230 Heatsink overheat protection
4240 Overload protection
4250, 4255 Overcurrent relay trip
5110 Heatsink temperature sensor failure (THHS)
5301 Current sensor/circuit failure
5102 Subcool heat exchanger bypass outlet temperature sensor failure
5103 Pipe temperature sensor failure
5104 Discharge temperature sensor failure
5105 Accumulator inlet temperature sensor failure
5106 Subcool heat exchanger liquid outlet sensor failure
5107 Outside air temperature sensor failure
4102 Open phase
4115 Power supply sync signal abnormality
OC failure
pattern
Trouble
OC
Normal
OS
Cooling
Permitted Permitted
Emergency
operation
Heating
Permitted Permitted
Maximum total capacity
of indoor units (Note 1)
OC failure OS1 failure OS2 failure
pattern pattern pattern
Trouble Normal Normal
Normal Trouble Normal
Normal Normal Trouble
Permitted Permitted Permitted
Permitted Permitted Permitted
60%
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Error code description
OS failure
pattern
Normal
Trouble
60%
OC, OS1 failure OC, OS2 failure
pattern pattern
Trouble Trouble
Trouble Normal
Normal Trouble
Permitted Permitted
Permitted Permitted
40%
OS1, OS2 failure
pattern
Normal
Trouble
Trouble
Permitted
Permitted
GB