Daikin Aurora Series, Руководство по обслуживанию

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Special Control SiUS341802E
61 Functions and Control
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 R3T
7.2.1 Oil Return Operation in Cooling Operation
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 cumulative operating time reaches 2
hours after power supply is turned ON and then every 8 hours.)
Furthermore, the cumulative oil feed rate is computed from Tc, Te, and compressor loads.
Part Name Electric Symbol Oil return operation
Inverter compressor M1C Constant low pressure control
Inverter fan M1F, M2F For heat exchanger mode
Electronic expansion valve (Heat exchanger
upper)
Y1E
Same as normal operation
Electronic expansion valve (Heat exchanger
lower)
Y3E
Electronic expansion valve (Subcooling
heat exchanger)
Y2E 0 pulse
Electric expansion valve (Subcooling
injection)
Y4E 760 pulse
Electronic expansion valve (Refrigerant
cooling)
Y5E Same as normal operation
Electronic expansion valve (Receiver gas
purge)
Y7E 0 pulse
Solenoid valve (Oil separator oil return) Y1S ON
Solenoid valve (Hot gas bypass) Y2S Same as normal operation
Solenoid valve (Liquid shutoff) Y3S ON
Four way valve (HP/LP gas pipe) Y4S Hold
Four way valve (Heat exchanger lower) Y5S Hold
Four way valve (Heat exchanger upper) Y6S Hold
Solenoid valve (Accumulator oil return) Y7S Same as normal operation
Ending condition
•
A lapse of 3 minutes
•
TsA – Te < 3
°
C (5.4°F)
•
A lapse of 12 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
Stopping unit OFF
Thermostat OFF unit Remote controller setting
Electronic expansion valve
Thermostat ON unit Normal control
Stopping unit 224 pulse
Thermostat OFF unit Forced thermostat ON (PI control)