E 150 1/2 Ton Van V6-4.2L VIN 2 (1997)
Expansion Block/Orifice Tube: Description and Operation
NOTE: The A/C evaporator core orifice is replaced as an assembly and should also be replaced whenever the A/C compressor is replaced.
The A/C evaporator core orifice is the restriction in the refrigerant system that creates the pressure drop necessary for cooling by metering the flow of
liquid refrigerant into the A/C evaporator core. The inlet filter screen acts as a strainer for the liquid refrigerant flowing through the A/C evaporator core
orifice. O-rings prevent the high-pressure liquid refrigerant from bypassing the A/C evaporator core orifice.
