Mitsubishi Electric PURY-80TMU Service Handbook page 40

(2) BC controller
Fan
Solenoid valve OFF,
LEV fully closed.
Note : 1 Two error modes include indoor unit side trouble, BC controller trouble, and outdoor unit side trouble. In the case of indoor
unit side trouble, error stop is observed in the concerned indoor unit only, and in the cases of BC controller and outdoor unit
side troubles, error stop is observed in all the indoor units, BC controller, and outdoor unit.
Start
Breaker
turned on
YES
Operation
command
NO
YES
1. Operation mode judgement
(cooling-only, heating-only,
cooling/heating mixed)
2. Transmission to outdoor unit
Receiving operation mode
command from outdoor unit
Error mode
NO
Operation mode
Operation mode
Cooling-only Heating-only
operations operations
NO
Note : 1
YES
Cooling/heating mixed
Operation mode
Cooling-main Heating-main
operations operations
–39–
Normal operations
Trouble observed
Stop
Error stop
Error code blinks on the
outdoor controller board
Error command to
BC controller
Error code blinks on the
remote controller