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Expansion Valve: Service and Repair

Expansion Valve And Remote Bulb:




Expansion Valve Operation:




Expansion Valve Pressure/Temperature Relationship Chart:






Remove or Disconnect

1. Evaporator from vehicle.
2. Expansion valve from evaporator.

Inspect

Tool Required:
J 39183-C R-134a Manifold Gage Set

1. Connect the expansion valve to a J 39183-C; connect the gages set's charging hose to a Refrigerant-134a refrigerant drum.
2. Soak the valve's remote bulb in water.
3. Close both the high and low-pressure valves.
4. Open the valve to the refrigerant drum.
5. Open the high-pressure valve to approximately 5 kg/sq cm2 (70 psi).
6. Read the pressure indicated on the low-pressure gage, and measure the water temperature with a thermometer.
7. The pressure/temperature relationship should fall within the specifications shown in Figure. Otherwise, replace the expansion valve.

Install or Connect

1. Expansion valve to evaporator.
2. Evaporator case to vehicle.