Daikin RTSQ20PY1 Service Manual page 74

Refrigerant Circuit
FXMQ125MFV1~250MFV1
Th2
Distributor
Filter
Main Control Equipment
Code Symbol
Electronic expansion valve Used to control the flow rate of refrigerant, and make the SH control while
A Y1E
B Y1S Solenoid valve
C - Capillary tube
* SH control: Superheated control of heat exchanger outlet
Thermistor
Code Symbol
Suction air temperature
Th1 R1T
thermistor
Liquid pipe temperature
Th2 R2T
thermistor
Gas pipe temperature
Th3 R3T
thermistor
Discharge air temperature
Th4 R4T
thermistor
63
Heat exchanger
M
Fan
Th1
(A)
Filter
Electronic
expansion valve
Name
in cooling or the SC control while in heating.*
Used to bypass hot gas while in heating with thermostat OFF.
Used to reduce pressure from high to low in bypassing hot gas.
SC control: Subcooling control of heat exchanger outlet
Name
Used to turn ON or OFF the thermostat and select cooling or heating
operation.
Used to control the opening degree of EV (Y1F) under the SC control.
Used to control the opening degree of EV (Y1E) under the SH control.
Used to control the electronic expansion valve opening and thermostat ON/
OFF so as to keep the discharge air temperature at the set temperature.
Th4
Th3
Filter
Capillary
(C)
tube
Solenoid
(B)
valve
Check
valve
Main function
Main function
SiBE31-801_C
Gas pipe
connection port
Liquid pipe
connection port
4D018650C
Refrigerant Circuit