Oil Return Control - Daikin VRV X RXQ6-48ANR Series Service Manual

SiME341909EA
7.2

Oil Return Control

In order to prevent the compressor from running out of oil, the oil return control 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
 Oil return control is not conducted before 2 hours have elapsed from the activation of power
 After 2 hours have elapsed, oil return control starts when the following item meets the
 Total amount of oil discharged from the compressor
(The total amount of oil discharged from the compressor is computed from Tc, Te, and
compressor loads.)
 Oil return control starts every 8 hours of cumulative operation of the compressor, even if the
Part Name
Compressor 1
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
supply.
reference value.
reference value is not met.
Electric
RXQ6/8AR
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
RXQ10/12AR RXQ14/16AR
 
—

 
 
 
 
 
—

Cooling oil return control
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 control.
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