System Performance Test

1. Install manifold gauge set, Fig. 3.
2. Place dry-bulb thermometer in center ventilator outlet.
3. Place wet and dry-bulb thermometers at blower inlet.
4. Open all doors, then run engine at a constant 1500 RPM.
5. Push A/C auto switch to On position.
6. Using temperature switch, set temperature to 65°F.
7. Operate A/C system until output temperature stabilizes. Ensure reading on pressure gauge is as follows:
a. On Millennia models, high pressure should be 160 - 240 psi.
b. On 929 models, pressures should be as specified in Fig. 4.

8. Read wet and dry bulb thermometer at blower inlet, then calculate relative humidity using Fig. 1.
9. Read dry-bulb thermometer at air outlet, then calculate temperature difference between center ventilator outlet and blower inlet.
10. If intersection of temperature difference and relative humidity is within range shown in Fig. 2, air conditioning system is operating satisfactorily.

Fig. 3 Manifold Gauge Set Installation:

Fig. 4 Refrigerant system Pressure Chart: