Operation Mode
1. Operation Mode
Indoor unit stop or
thermostat OFF
Startup control
• Cooling startup
• Heating startup
Normal operation
• Compressor PI control
• Electronic expansion
valve PI control
• Protection control
40
Operation in
stop mode
Indoor unit thermostat ON
Pressure
equalization
prior to startup
control
control
Cooling or heating
operation
Yes
Oil return IN
conditions are met.
No
Yes
Defrost IN
conditions are met.
No
Yes
Operation
mode change
No
Malfunction/Standby
Indoor unit stop or
thermostat OFF
Indoor unit thermostat ON
Malfunction/Standby
Indoor unit stop or
thermostat OFF
Malfunction/
Standby
Note:
In the event indoor unit stops or the thermostat
turns OFF while in oil return operation or
defrosting operation, pump-down residual
operation is performed on completion of the oil
return operation or defrosting operation.
Restart standby
(Compressor stop)
Pump-down
residual
operation
Oil return operation
Defrosting operation
SiENBE34-703
Malfunction/
Standby
(V3152)
Function