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Expansion Valve: Service and Repair

Expansion Valve Operation:




Expansion Valve Pressure/Temperature Relationship Chart:






Remove or Disconnect

1. Evaporator from vehicle.

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-13 4a 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.cm (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

8. Evaporator to vehicle.