Expansion Block/Orifice Tube: Description and Operation

NOTE: The A/C evaporator core orifice should be replaced whenever an A/C compressor is replaced.

A/C Evaporator Core Orifice:

DESCRIPTION
The evaporator core orifice has the following characteristics:
^ It is color-coded orange.
^ It has a diameter of 1.46 mm (0.058 inch).
^ It has filter screens located on the inlet and outlet ends of the tube body.

OPERATION
The A/C evaporator core orifice assembly is the restriction in the refrigerant circuit that creates the pressure drop necessary for cooling by metering the flow of liquid refrigerant into the A/C evaporator core, thereby reducing the pressure. Operation is as follows:
^ The Inlet filter screen acts as a strainer for the liquid refrigerant flowing through the A/C evaporator core orifice.
^ O-rings on the A/C evaporator core orifice prevent the high-pressure liquid refrigerant from bypassing the A/C evaporator core orifice.
^ Adjustment or service cannot be made to the A/C evaporator core orifice assembly.
^ The condenser to evaporator tube must be replaced, or an Orifice Tube Replacement Kit E5VY-19D695-A or equivalent installed, if replacement of the A/C evaporator core orifice is necessary.