Specifications
Table Of Contents
- Cover
- Table of Contents
- Part 1 General Information
- Part 2 Specifications
- Part 3 Refrigerant Circuit
- Part 4 Function
- Part 5 Test Operation
- Part 6 Troubleshooting
- Part 7 Appendix
- 1. Piping Diagrams
- 2. Wiring Diagrams for Reference
- 3. List of Electrical and Functional Parts
- 4. Option List
- 5. Piping Installation Point
- 6. Example of connection (R-410A Type)
- 7. Thermistor Resistance / Temperature Characteristics
- 8. Pressure Sensor
- 9. Method of Checking the Inverter’s Power Transistors and Diode Modules
- Part 8 Precautions for New Refrigerant (R-410A)
- Index
- Drawings & Flow Charts
Refrigerant Circuit Si34-704
68 Refrigerant Circuit
1.5 Outdoor air processing unit FXMQ125MFV1~250MFV1
1.5.1 Refrigerant System
Main Control Equipment
∗
SH control: Superheated control of heat exchanger outlet
SC control: Subcooling control of heat exchanger outlet
Thermistor
4D018650B
Th4
Th3
Th2
Th1
A
B
C
Code Symbol Name Main function
AY1EMotorized valve
Used to control the flow rate of refrigerant, and
make the SH control while in cooling or the SC
control while in heating.∗
B Y1S Solenoid valve
Used to bypass hot gas while in heating with
thermostat OFF.
C — Capillary tube
Used to reduce pressure from high to low in
bypassing hot gas.
Code Symbol Name Main function
Th1 R1T
Suction air temperature
thermistor
Used to turn ON or OFF the thermostat and select
cooling or heating operation.
Th2 R2T
Liquid pipe temperature
thermistor
Used to control the opening degree of EV (Y1F)
under the SC control.
Th3 R3T
Gas pipe temperature
thermistor
Used to control the opening degree of EV (Y1E)
under the SH control.
Th4 R4T
Discharge air
temperature thermistor
Used to control the electric expansion valve
opening and thermostat ON/OFF so as to keep the
discharge air temperature at the set temperature.