Daikin VRV II RXYQ5MATL, Service Manual, Page: 89 / 331

Special Control Si39-504
78 Function
3.2 Oil Return Operation
In order to prevent the compressor from running out of oil, the oil return operation is conducted to recover oil flown out
from the compressor to the system side.
3.2.1 Oil Return Operation in Cooling Operation
[Start conditions]
Referring to the set conditions for the following items, start the oil return operation in cooling.
• Cumulative oil feed rate
• Timer setting (Make this setting so as to start the oil return operation when the initial cumulative operating time
reaches two hours after power supply is turned ON and then every eight hours.)
Furthermore, the cumulative oil feed rate is computed from Tc, Te, and compressor loads.
* In the case of multi-outdoor-unit system,
Master unit: Performs the operations listed in the table above.
Slave units: Operating units perform the operations listed in the table above.
Non-operating units perform the operations listed in the table above from the oil return operation.
(Non-operating unit stops during “oil return preparation operation”.)
* Actuators are based on RXYQ16MA.
Outdoor unit actuator
Oil return preparation
operation
Oil return operation Post-oil-return operation
Compressor Upper limit control
177 Hz + OFF + OFF
Lapse of 20 sec.
Pe<5.5k
⇒
Inv 25 Step Down
Pe>6.5k
⇒
1 Step Up
52 Hz + OFF + OFF
Outdoor unit fan Fan control Fan control Fan control
Four way valve OFF OFF OFF
Main motorized valve (EV1) 2000 pls 2000 pls 2000 pls
Subcooling motorized valve (EV2) SH control 0 pls 0 pls
Hot gas bypass valve (SVP) OFF ON ON
Receiver gas discharging valve
(SVG)
OFF OFF OFF
Non-operating unit liquid pipe stop
valve (SVSL)
ON ON ON
Ending conditions 20 sec.
•
3 min.
•
Ts - Te<5
°
C
•
3 min.
•
Pe<0.4MPa
•
HTdi>110
°
C
or
or
Indoor unit actuator Cooling oil return operation
Fan
Thermostat ON unit Set flow rate (subject to the situation)
Stopping unit OFF
Thermostat OFF unit OFF
Electronic expansion valve
Thermostat ON unit Normal opening
Stopping unit 200 pls
Thermostat OFF unit 200 pls