Daikin VRV EMERION RXYQ-AATJA, Service Manual

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SiUS342303E Special Control
Part 4 Functions and Control 116
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
TsA: Suction pipe temperature detected by thermistor R5T
Ts: Suction pipe before accumulator temperature
7.2.1 Oil Return Operation in Cooling Operation
Part name
Electric
symbol
Function of functional part
Compressor motor M1C, M2C Constant low pressure control
Fan motor M1F, M2F High pressure control
Electronic expansion valve (Heat exchanger main) Y1E Same as normal control
Electronic expansion valve (Heat exchanger left) Y6E
Electronic expansion valve (Refrigerant cooling IPM) Y2E Same as normal control
Electronic expansion valve (Subcooling heat exchanger) Y3E 0 pulse
Electronic expansion valve (Refrigerant auto charge) Y4E 40 pulse
Electronic expansion valve (Refrigerant cooling air) Y5E Same as normal control
Solenoid valve (Oil separator oil return) Y1S, Y2S ON
Solenoid valve (Hot gas bypass) Y3S Same as normal control
Solenoid valve (Accumulator oil return) Y4S ON
Solenoid valve (Four way valve) Y5S Hold
Solenoid valve (Injection) Y6S ON
Ending condition
A lapse of 3 minutes
TsA – Te < 3 C (5.4°F)
A lapse of 6 minutes while the frequency is
more than that of oil return operation.
&
OR
Indoor unit actuator Oil return operation
Fan
Thermostat ON unit Remote controller setting
Non-operating unit OFF
Thermostat OFF unit Remote controller setting
Electronic expansion valve
Thermostat ON unit Normal control
Non-operating unit 224 pulse
Thermostat OFF unit Forced thermostat ON (PI control)
Low-temperature hydrobox unit actuator Oil return operation
Pump
Thermostat ON unit Normal control
Non-operating unit Normal control
Thermostat OFF unit Normal control
Electronic expansion valve
Thermostat ON unit Normal control
Non-operating unit 224 pulse
Thermostat OFF unit Forced thermostat ON (PI control)