Daikin REYQ72, Serveice Manual

Page: 61 / 273

Special Control SiUS39-602
50 Function
3.2 Oil Return Operation
In order to prevent the running-out of refrigerating machine oil in the compressor, the oil flowing
out from the compressor to the system side is collected through the oil return operation.
3.2.1 Oil Return Operation in Cooling Operation
[Starting conditions]
Start oil return operation in cooling operation referring to the following conditions.
* Cumulative oil return amount
* Timer
Cumulative compressor operating time after power supply turns on exceeds 2 hours and the
time after the completion of previous oil return operation exceeds 8 hours.
Furthermore, the cumulative oil return is calculated according to Tc, Te, and compressor load.
Actuator
Oil return preparation
operation
Oil return operation Post-oil-return operation
Compressor Upper limit control 124 Hz + ON 52 Hz + OFF
Outdoor unit fan Fan control Fan control Fan control
Four way valve 1 OFF OFF OFF
Four way valve 2 OFF OFF OFF
Main motorized valve (EV1) 1400 pls 1400 pls 1400 pls
Sub motorized valve (EV2) 1400 pls 1400 pls 1400 pls
Sub-cooling motorized valve (EV3) SH control 0 pls 0 pls
Hot gas bypass valve (SVP) OFF ON ON
Oil equalization valve (SVO) ON ON ON
Receiver gas charging valve (SVL) OFF OFF OFF
Receiver gas discharge valve (SVG) OFF OFF OFF
Discharge pipe stop valve (SVR) OFF OFF OFF
Non-operating unit liquid pipe stop
valve (SVSL)
OFF OFF OFF
High pressure gas pipe pressure
reduction valve (SVC)
ON ON ON
Ending conditions 1 min.
•
6 min.
•
Ts - Te<9
30 sec.
or
Indoor unit actuator Cooling oil return operation
Fan
Thermostat ON unit Set Air Volume
Stopping unit OFF
Thermostat OFF unit OFF
Electronic expansion valve
Thermostat ON unit Normal opening
Stopping unit 200 pls
Thermostat OFF unit 200 pls