Operation Mode
SiUS28-902_B
12
Function
1. Operation Mode
Startup control
•
•
Oil return operation
Yes
Yes
No
No
Error/Standby
Normal operation
• Compressor PI control
•
• Protection control
Indoor unit thermostat ON
No
Yes
Defrosting operation
Indoor unit thermostat ON
Error/Standby
Error/Standby
Operation in
stop mode
Pressure
equalization
prior to startup
Indoor unit stop or
thermostat OFF
Cooling startup
control
Heating startup
control
Electronic expansion
valve PI control
Cooling or heating
operation
Oil return starting
conditions are met.
Defrost starting
conditions are met.
Operation
mode change
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.
Indoor unit stop or
thermostat OFF
Indoor unit stop or
thermostat OFF
Error/
Standby
Pump down
residual
operation
Restart standby
(Compressor stop)