A/C Performance Test

Review Safety Precautions and Warnings before proceeding with this procedure. Air temperature in test room and on vehicle must be 21 °C (70 °F) minimum for this test.

NOTE: When connecting the service equipment coupling to the line fitting, verify that the valve of the coupling is fully closed. This will reduce the amount of effort required to make the connection.

1. Connect a tachometer and manifold gauge set. Attach a thermal couple to the evaporator line.
2. Set control to A/C, temperature lever on full cool and blower on high.
3. Start engine and hold at 1000 rpm with A/C clutch engaged.
4. Engine should be warmed up.

NOTE: Verify water valve is in the closed position. Check both heater hoses at cowl, past the water valve. The hoses should be cool to the touch. To verify the valve is functioning, remove cable at the valve. Open the water valve. Check temperature of hoses. Hose temperature should increase instantly.

5. Insert a thermometer in the A/C outlet and operate the engine for five minutes. The A/C clutch may cycle depending on ambient conditions.

A/C Performance Temperature Chart:

6. With the A/C clutch engaged, compare the discharge air temperature to the A/C Performance Temperature Chart.
7. If the discharge air temperature fails to meet the specifications. Refer to the System Charge Level.