Expansion Block/Orifice Tube: Service and Repair

REMOVE OR DISCONNECT
1. Discharge A/C system.
2. Loosen nut and separate liquid line from evaporator inlet pipe.
3. Carefully remove orifice tube with needle-nosed pliers or proper orifice removal tool. In the event that difficulty is encountered during the removal of a restricted or plugged expansion tube (orifice tube), the following procedure is recommended:

a. Remove as much of any impacted residue as possible.
b. Carefully apply heat with heat gun (hair drier, epoxy drier or equivalent) approximately 7 mm (1/4 inch) from dimples on inlet pipe. Do not overheat pipe.

NOTE: If the system has a pressure switch near the orifice tube location, it should be removed prior to heating the pipe to avoid damage to switch.

c. While applying heat, use proper orifice removal tool to grip the orifice tube. Use a turning motion along with a push-pull motion to loosen to the impacted orifice tube and remove it.

INSTALL OR CONNECT
1. New orifice tube, with short screen toward the evaporator.
2. Reassemble liquid line to evaporator inlet pipe and torque nut to 24 Nm (17 lbs. ft.).
3. Evacuate and recharge A/C system with 1.02 kg (2.25 lbs.) of R-12 refrigerant.
4. Leak test