Daikin VRV II REYQ8MY1B, Service Manual

Page: 83 / 309

Special Control Si39-306
72 Function
3.2.2 Oil Return Operation in Heating Operation
[Starting conditions]
Start oil return operation in heating operation referring to the following conditions.
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. And cumulative oil
return is calculated based on To, Te compressor load.
*
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 performs the operations listed in the table above from the “oil return operation”.
*
Actuators are based on REYQ16M.
<In condition of oil return operation>
Compressor cumulative operation time > 8 hours
(However, 2 hours after turning power on first time.)
Actuator
Oil return preparation
operation
Oil return operation Post-oil-return operation
Compressor Upper limit control 124 Hz + ON + OFF
1-step increase from
(74Hz + OFF + OFF) to
(Pc - Pe > 0.4 MPa) time.
Outdoor unit fan
STEP8
or
STEP9
OFF STEP9
Four way valve 1 Heat exchange mode OFF ON
Four way valve 2 Heat exchange mode OFF OFF
Main motorized valve (EV1)
Four way valve 1
OFF:1400 pls
ON:SH control
0 pls 180 pls
Sub motorized valve (EV2)
Four way valve 2
OFF:1400 pls
ON:SH control
0 pls 1400 pls
Sub-cooling motorized valve (EV3) 0 pls 0 pls 0 pls
Hot gas bypass (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 gas stop valve (SVR) ON OFF OFF
Non-operating unit liquid pipe stop
valve (SVSL)
ON OFF OFF
High pressure gas pipe pressure
reduction valve (SVC)
OFF ON ON
Ending conditions 2 min.
•
6 min.
•
Ts - Te<5
•
160 sec.
•
Pc - Pe>0.4MPa
or or
Indoor unit actuator Heating oil return operation
Fan
Cooling Thermostat ON unit Set Fan Speed
Heating Thermostat ON unit OFF
Stopping unit OFF
Thermostat OFF unit OFF
Electronic expansion valve
Thermostat ON unit 512 pls
Stopping unit 512 pls
Thermostat OFF unit 512 pls