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Fault Handling
4.Four-way reversing valve
A. Basic structure of four-way reversing valve
The four-way reversing valve mainly consists two parts: coil and valve body, as shown below:
B. Working principle of four-way reversing valve
Working principle:
When the solenoid coil is off, the compression spring at the right side will drive the pilot valve to move leftwards; high pressure gas will enter the
capillary (1) before entering the piston chamber at right end. In the meantime, the gas in the piston chamber at left end will be discharged. The
piston and the main valve will move to leftwards due to the pressure difference between the two ends so that the air exhaust pipe is connected
with outdoor unit and the other two pipes are also connected to create a cooling cycle.
When the solenoid coil is on, the magnetic effect generated by the solenoid coil will overcome the force of the compression spring and drive
the pilot valve to move rightwards; high pressure gas will enter the capillary (1) before entering the piston chamber at left end. In the meantime,
the gas in the piston chamber at right end will be discharged. The piston and the main valve will move to rightwards due to the pressure dif
-
ference between the two ends so that the air exhaust pipe is connected with indoor unit and the other two pipes are also connected to create
a heating cycle.
Compressor
Valve Body
Pllot Valve
Solenold Coll
Pllot Valve
Compressor
Valve Body
Condensor
Evaporator
Solenold Coll
D
S
E
C
D
S
E
C
Condensor
Evaporator
制冷模式（断电）
制热模式（得电）
Heating mode (power on)
制热模式
Cooling mode (power off)
