Panasonic Urban Multi MX1R Series, Service Manual, Page: 579 / 643

Backup and Emergency Operation PACD011001C2
558 Special Service Mode UM Combination “MA1R Series” Using R-407C
1. Backup and Emergency Operation
1.1 Backup and Emergency Operation
1.1.1 Backup Operation :
When a constant speed type compressor malfunctions due to OC actuation, if you restart operation by
remote controller after the unit stops, you can continue to operate the system without the faulty constant
speed type compressor.
The system can run by backup operation for up to 3 hours of total indoor unit operating time. When 3 hours
is exceeded and the malfunction still remains, the system once again stops due to malfunction. If the
malfunction returns to normal, the system continues to operate as is.
Backup Operation
Control Flow
After the system briefly stops due malfunction in order to call attention to the problem, backup operation is
started by remote controller.
For the reason described above, after about 3 hours of backup operation, the system again carries out
malfunction detection, and the system once again stops due to malfunction if an error is detected.
Note: 1. < For 2-compressor system >
„
When the STD compressor OC operates, the operation continues using only the inverter compressor
based on remote control reset. (for 3 hours only)
< For 3-compressor system >
„
When OC operates again immediately after a backup operation (within 5 minutes after STD compressor
startup), STD1 and STD2 are switched and operation is retried.
„
If OC activates again, only the inverter compressor is used for the operation.
„
(In any case, the backup operation ends after 3 hours.)
„
The compressor in which OC is activated is prohibited to operate until power reset is conducted for a
restart.
Malfunction occurs.
(MF168)
Malfunction detection
System stops due to malfunction.
Backup operation starts.
Operates without faulty constant
speed (STD) compressor. (Note 1)
Returns to normal operation.
No malfunction
3 hours elapse.
Remote controller reset
Malfunction
occurs again.