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MUL
TI V 5 Outdoor Unit Service Manual
Due to our policy of continuous product innovation, some specifications may change without notification.
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Checking the Four-Way Reverse Valve
1. The four-way reverse valve must be OFF before the outdoor and
indoor units are powered up and turned on.
2. The four-way reverse valve must be OFF during cooling, defrost,
and oil recovery operation. The four-way reverse valve must be
ON during heating operation.
3. When switching from cooling to heating operation, the four-way
valve position changes during the three minute mode change
restart.
4. To check if the four-way reverse valve is operating in cooling
or heating mode, touch the piping surface of the low pressure
service valve.
5. See diagram at right for the refrigerant flowchart of the four-way reverse valve.
6.
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500V]).
Figure 62: Refrigerant Flowchart of the Four-Way Reverse Valve.
Heating Operation
Outdoor Heat
Exchanger
Outdoor Heat
Exchanger
D : Discharge
E : Evaporator
C : Condensor
S : Suction
Indoor Heat
Exchanger
Cooling Operation
Checking the Temperature Sensors
• Outdoor Temperature Sensor: TH1
• Pipe Temperature Sensor: TH2
• Discharge Pipe (D-pipe) Temperature Sensor: TH3
1. Check the temperature sensor installation and connections.
2. Check if the connection contact of the temperature sensor is normal.
3. Measure the resistance of temperature sensor.
Temperature Sensor
TH1
TH2
TH3
Resistance
.ȍ#)
.ȍ#)
.ȍ#)
.ȍ#)
.ȍ#)
.ȍ#)
Table 67: Temperature Sensor Resistance Values.
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TEMPERATURE SENSORS