Operation Flowchart (Outdoor Unit) - Daikin VRV RXYQ72-384XAYCA Service Manual

SiUS342004EB

1. Operation Flowchart (Outdoor Unit)

For detailed description of each function in the flow below, refer to the details on related function on
the following pages.
Stop control
(1) Stop due to error
(2) When system is in stop control
(3) Slave unit stops during master unit control
Standby control
(1) Restart standby
(2) Crankcase heater control
Startup control
(include pressure equalization before startup)
(1) Startup control in cooling
(2) Startup control in heating
Basic control
(1) Normal Operation
(2) Compressor PI control
(3) Operation priority and rotation of
compressors
(4) Compressor step control
(5) Electronic expansion valve PI control
(6) Step control of outdoor fans
Protection control
(1) High pressure protection control
(2) Low pressure protection control
(3) Discharge pipe protection control
(4) Compressor body protection control
(5) Inverter protection control
Note(s)
1. If the indoor unit stops or the thermostat turns OFF while in oil return operation or defrost
2. Not performed during cooling mode.
Part 4 Functions and Control
Thermostat ON
End of
startup
control
Conditions met for oil return
Conditions met for defrosting
operation, pump down residual operation is performed on completion of the oil return operation
or defrost operation.
Operation Flowchart (Outdoor Unit)
Special control
(1) Pump down residual operation
(note 2)
Thermostat OFF
(2) Oil return operation (note 1)
(3) Defrost operation (note1)
(4) Outdoor unit rotation
82