Oil Return Operation - Daikin RXQ12AHR Service Manual

SiAF341904E
7.2

Oil Return Operation

In order to prevent the compressor from running out of oil, the oil return operation is conducted
to recover oil that has flowed out from the compressor to the system side.
Tc : High pressure equivalent saturation temperature
Te : Low pressure equivalent saturation temperature
Ts: Suction pipe temperature detected by thermistor R3T
Starting 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
Furthermore, the cumulative oil feed rate is computed from Tc, Te, and compressor loads.
Part Name
Inverter compressor 1
Inverter compressor 2
Inverter fan 1
Inverter fan 2
Electronic expansion valve
(Injection)
Electronic expansion valve
(Refrigerant auto charge)
Solenoid valve (Oil return 1)
Solenoid valve (Oil return 2)
Ending conditions
Fan
Electronic expansion valve
Part 4 Functions and Control
cumulative operating time reaches 2 hours after power supply is turned ON and then every 8
hours.)
Electric
RXQ6-12A
Symbol
M1C

M2C —
M1F

M2F —
Y2E

Y4E

Y3S

Y4S —
Indoor unit actuator
Thermostat ON unit
Non-operating unit
Thermostat OFF unit
Thermostat ON unit
Non-operating unit
Thermostat OFF unit
RXQ14A RXQ16-20A
 
—

 
 
 
 
 
—

Cooling oil return operation
Remote controller setting
OFF
Remote controller setting
Normal control
224 pulse
Normal control with forced thermostat
ON
Special Control
Function of Functional Part
Capacity step PI control
TC control
0 pulse
480 pulse
ON
· A lapse of 3 minutes.
&
· Ts1–Te < 3°C
OR
· A lapse of 6 minutes
while the frequency
is more than that of
oil return operation.
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