A/C Performance Testing

Fig. 7 Temperature Pressure Relationship Chart:

1. Connect pressure gauge and manifold assembly to the compressor service valves and close both valves on gauge and manifold assembly.
2. Open both service valves to the mid-position.
3. Operate the system with engine at 1500 RPM and controls set for full cooling but not to the "Max" or "Cold" detent.
4. Insert a thermometer in the discharge air outlet and observe the air discharge temperature, then compare pressure and temperature to chart.