Daikin VRV-WIII RWEYQ72PTJU Service Manual page 69

SiUS30-1301
7.1.2 Oil Return Operation in Heating or Cooling/Heating Simultaneous
Operation
Tc: High pressure equivalent saturation temperature
Te: Low pressure equivalent saturation temperature
[Starting conditions]
Start oil return operation in heating 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 Tc, Te compressor load.
Parts Name
Inverter compressor
Four way valve (Main)
Four way valve (Sub)
Electronic expansion
valve (Main)
Electronic expansion
valve (Subcooling)
Solenoid valve (Hot
gas)
Solenoid valve (Oil
return of water heat
exchanger)
Solenoid valve
(Receiver gas
charging)
Solenoid valve
(Receiver gas
discharging)
Solenoid valve (Non-
operating unit liquid
pipe closing)
Indoor unit fan
(Cooling)
Indoor unit electronic
expansion valve
(Cooling)
Indoor unit fan
(Heating)
Indoor unit electronic
expansion valve
(Heating)
Ending condition
Cooling Branch Selector unit
actuator
Electronic expansion valve (EVH)
Electronic expansion valve (EVL)
Electronic expansion valve (EVHS)
Electronic expansion valve (EVLS)
Electronic expansion valve (EVSC)
Function and Control
Electric
Symbol
Symbol
— M1C
20S1 Y5S
20S2 Y7S
EV1 Y1E
EV3 Y3E
SVP Y1S
SVE Y2S
SVL Y3S
Same as normal
heating operation
SVG Y4S
SVSL Y6S
— M1F, M2F
EV Y1E
— M1F, M2F
EV Y1E
Electric
Oil return operation
symbol
Y4E 600pulse
Y5E 760pulse (fully open)
Y2E 480pulse (fully open)
Y3E 480pulse (fully open)
Y1E 0pulse
During Oil Return
Preparation
Operation
104 Hz
OFF
OFF
2000 pulse
0 pulse
ON
OFF
OFF
OFF
ON
Thermostat ON/OFF:
Indoor unit control
Thermostat OFF:
OFF
320 pulse
OFF
320 pulse
2 minutes Max. 8 minutes
Heating Branch Selector unit
actuator
Electronic expansion valve (EVH)
Electronic expansion valve (EVL)
Electronic expansion valve (EVHS)
Electronic expansion valve (EVLS)
Electronic expansion valve (EVSC)
Special Operation
After Oil Return
Operation
74 Hz
ON
Heat exchanger mode
Y7S = OFF: 2000 pulse
Y7S = ON : 180 pulse
0 pulse
ON
OFF
OFF
OFF
ON
Normal control
Normal control
Indoor unit control
Normal control
Max. 3 minutes
Electric
Oil return operation
symbol
Y4E 600pulse
Y5E 760pulse (fully open)
Y2E 480pulse (fully open)
Y3E 480pulse (fully open)
Y1E 0pulse
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