LiuGong CLG835H, Service Manual

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5-6
Structure Function Principle
January 24, 2017
Description of principle diagram and working principle CLG835H
Description of principle diagram and working principle
Air conditioner of this machine is vapor compression type refrigeration air conditioner, refer to
its working process and principle as follows:
(1) Compression process
Refrigerant absorbs heat in the evaporator and then changes into low-temperature low-pressure
refrigerant vapor, which is sucked into the compressor, where it is compressed into high-temperature
high-pressure refrigerant vapor, and then is discharged into the condenser.
(2) Condensation process
After high-temperature and high-pressure gaseous refrigerant enters condenser, the air, driven by
the engine radiator fan, passes across condenser surface to bring away heat of refrigerant. The
refrigerant is condensed into medium-temperature and high-pressure liquid type.
(3) Throttling process
Medium-temperature and high-pressure refrigerant liquid is filtered by dryer and then throttled
through the expansion valve (refrigerant is sprayed from the pores of expansion valve and expanded
suddenly). It changes into low-temperature and low-pressure refrigerant mist for entering the evapo-
rator.
(4) Evaporator process
Low-temperature and low-pressure refrigerant liquid formed by the throttling of expansion valve is
vaporized in the evaporator, the air in the car is driven by the evaporator fan unit to flow through the
evaporator surface. The refrigerant absorbs the heat of air in the car, thus to reduce the air tempera-
ture, and dissolve out condensate water. Refrigerant absorbing heat is evaporated into low-tempera-
ture and low-pressure refrigerant vapor, which is sucked into the compressor and compressed again,
so that one refrigeration cycle is completed.
The compressor keeps rotating, the above refrigeration process is cycled continuously. The heat in
the car is taken away by refrigerant in the evaporator, so as to complete cooling and dehumidification
of the complete vehicle.