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SiBE341027
Detailed Control Functions
Function
57
2.6
Special Control
2.6.1 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.
(1) Oil Return Operation in Cooling
[Start conditions]
Referring to the set conditions for the following items, start the oil return operation in cooling.
• 2 hours after initial power ON
• A lapse of every 1 ~ 2 hours during low-load operation
• A lapse of every 8 hours during high-load operation
*
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”.)
Part Name
Electric Symbol
Oil return operation
RQYQ8P
PQYQ10·12P
PQYQ14·16P
Compressor
M1C
M1C
M1C
177Hz
–
M2C
M2C
No instruction
→
OFF
–
–
M3C
No instruction
→
OFF
Outdoor unit fan
M1F
M1F
M1F, M2F
Fan control in normal cooling
(Heat exchanging mode)
Four way valve
Y3S
Y3S
Y3S
OFF
Electronic expansion valve (Main)
Y1E
Y1E
Y1E
480 pls
Electronic expansion valve (Main 2)
–
–
Y2E
Electronic expansion valve
(Subcooling)
Y2E
Y2E
Y3E
0 pls
Solenoid valve (Hot gas)
Y1S
Y1S
Y1S
ON
Solenoid valve (Receiver gas vent)
Y8S
Y8S
Y8S
OFF
Solenoid valve (Circuit of oil return)
Y5S
Y5S
Y5S
OFF
Solenoid valve (Close liquid pipe for
stopped outdoor unit)
Y6S
Y6S
Y6S
ON
Solenoid valve (Main electronic
expansion valve bypass)
Y10S
Y10S
–
ON
Solenoid valve (Refrigerant
regulator gas vent pipe)
Y11S
Y11S
Y10S
OFF
Solenoid valve (Refrigerant
regulator liquid pipe)
Y12S
Y12S
Y11S
OFF
Solenoid valve (Refrigerant
regulator gas pipe)
Y13S
Y13S
Y12S
OFF
Solenoid valve (Refrigerant
regulator liquid outlet)
Y14S
Y14S
Y13S
OFF
Solenoid valve (Receiver liquid level)
Y7S
Y7S
Y7S
OFF
Solenoid valve (Mixing unit inlet)
Y4S
Y4S
Y4S
OFF
Solenoid valve (Bypass)
Y2S
Y2S
Y2S
OFF
Solenoid valve (Oil regulator outlet)
Y9S
Y9S
Y9S
ON
Indoor unit actuator
Cooling oil return operation
Fan
Thermostat ON unit
Remote controller setting
Stopping unit
OFF
Thermostat OFF unit
OFF
Electronic expansion valve
Thermostat ON unit
Normal opening
Stopping unit
200 pls
Thermostat OFF unit
200 pls