Service manual

AUX air conditioner service manual
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The pressure switch used for the air-conditioner includes two types: high pressure switch and low
pressure switch. They are composed of the screw joint entry, thin shell film flake, dynamic contact
point, static contact point and mandril etc. Such as the picture 2-16：
The high pressure switch is fixed at the high pressure side of the refrigerating system. It shuts off the
main controlling circuit of the air-conditioner and stops the operation of the compressor in the event of:
the dust accumulation on the condenser’s wing blocks the air path, or the fan is damaged and the air
volume is insufficient, or the refrigerant is overcharged, or the air inside the system causes the
over-high pressure inside the pipeline. It will restart automatically after the pressure drops.
The low pressure switch is fixed at the low pressure side of the refrigerating system. It shuts off the
main controlling circuit and stops the operation of the air-conditioner for protecting the compressor in
the event of: the dust covers the evaporator’s wing, or the fan air volume is insufficient, or the
refrigerant is insufficient, or the surface of the evaporator is frosted, or the system is blocked, etc.,
which may cause the low air-sucking pressure at the low pressure side.