HVAC System (Heater, Ventilator and A/C)
EXPANSION VALVE
AC-35
15.Expansion Valve
A: LHD MODEL
1. MECHANISM
The expansion valve is connected to both the evaporator inlet and outlet pipes. It converts high-
pressure liquid refrigerant which comes from the receiver drier to misty, low-pressure refrigerant
which is delivered to the evaporator. Being at low pressure and low temperature, this refrigerant
can easily evaporate in the evaporator and remove heat from the cabin air. The valve performs this
conversion by automatically controlling the flow rate of refrigerant according to the cooling ability
required by the heat load.
The refrigerant temperature is sensed by the temperature sensing element located in the low-
pressure refrigerant passage of the expansion valve, and the flow rate of the refrigerant is con-
trolled by changing the lift of the valve ball located in the high-pressure passage.
From evaporator
(Low-pressure)
To evaporator
(Low-pressure)
H4H1123C
To Next Page
