A/C Performance Testing

Fig. 7 Performance Temperature Chart:

1. Connect a suitable manifold gauge set and tachometer.
2. Press auto. mode button on A/C control panel, then reset control buttons to max. cooling in manual mode as follows:
a. Place mode selection button in the face position.
b. Place temperature control buttons in max. cooling position.
c. Place air selection button in the "Recirc" position.
d. Place blower switch to high position.
3. Start engine, then adjust RPM to 1000 with compressor clutch engaged.
4. Vehicle doors should be closed, windows up and engine should be at normal operating temperature.
5. Insert a thermometer in the left center vent and allow engine to run for 20 minutes.
6. Note the discharge temperature and compare with chart. Reading should be taken with compressor clutch engaged.