Expansion Block/Orifice Tube: Description and Operation
Evaporator Core OrificeNOTE: A new evaporator core orifice should be installed whenever a new A/C compressor is installed.
The evaporator core orifice is located in the condenser-to-evaporator line, and can be removed through an access fitting. The evaporator core orifice provides a restriction to the flow of refrigerant from the high-pressure side of the refrigerant system and separates the low-pressure and high-pressure sides of the refrigerant system.
A/C Pressure Transducer
The A/C pressure transducer is used by the PCM to monitor the discharge pressure in the high-pressure side of the refrigerant system. When the A/C pressure transducer is reading a discharge pressure above acceptable levels, the PCM will disengage the A/C compressor clutch.
The A/C pressure transducer is installed on a Schrader-type valve core fitting on the compressor-to-condenser discharge line. It is not necessary to recover the refrigerant before removing the A/C pressure transducer.