Defrost Operation - Daikin VRV EMERION RXYQ-AATJA Service Manual

SiUS342303E
7.3

Defrost Operation

To defrost the outdoor heat exchanger while in Evaporator, the defrost operation is conducted to
recover the heating capacity.
Tb: Heat exchanger deicer temperature
Part name
Compressor motor
Fan motor
Electronic expansion valve (Heat exchanger main)
Electronic expansion valve (Heat exchanger left)
Electronic expansion valve (Refrigerant cooling IPM)
Electronic expansion valve (Subcooling heat exchanger)
Electronic expansion valve (Refrigerant auto charge)
Electronic expansion valve (Refrigerant cooling air)
Solenoid valve (Oil separator oil return)
Solenoid valve (Hot gas bypass)
Solenoid valve (Accumulator oil return)
Solenoid valve (Four way valve)
Solenoid valve (Injection)
Ending condition
Indoor unit actuator
Fan
Electronic expansion valve
Low-temperature hydrobox unit actuator
Pump
Electronic expansion valve
Part 4 Functions and Control
Electric
symbol
RXYQ72AA: 127.3 rps
RXYQ96/120AA: 125.4 rps + 140.0 rps
M1C, M2C
RXYQ144/168AA: 85.2 rps + 114.9 rps
RXYQ192/216/240AA: 135.0 rps + 140.0 rps
With high pressure
M1F, M2F
OFF ↔ Step 4 ↔ Step 6
Y1E 100%
Y6E
Y2E Same as normal control
Y3E Discharge temperature control
Y4E Minimum pulse
Y5E Same as normal control
Y1S, Y2S ON
Y3S ON
Y4S ON
Y5S OFF
Y6S ON
OR

Defrost operation

Thermostat ON unit
Non-operating unit
Thermostat OFF unit
Thermostat ON unit
Non-operating unit
Thermostat OFF unit
Oil return operation
Thermostat ON unit
Non-operating unit
Thermostat OFF unit
Thermostat ON unit
Non-operating unit
Thermostat OFF unit
Function of functional part
x
A lapse of 15 minutes
x
Tb > 11°C (51.8°F) continues for 60 seconds or more
OFF
OFF
OFF
Defrost EV opening degree
Defrost EV opening degree
Defrost EV opening degree
Normal control
Normal control
Normal control
0 pulse
0 pulse
0 pulse
Special Control
118