Performance Test

Fig. 2 Relative Humidity Graph:

Fig. 3 Typical System Performance Graph:

1. Connect manifold gauge set to high and low sides of system at compressor service valves.
2. Start engine and allow to run at approximately 2000 RPM, then activate air conditioner.
3. Set blower switch at ``HI,'' temperature lever at ``COOL'' and the selector levers at ``VENT'' and ``RECIR.''
4. Open all windows and doors, then position dry bulb thermometer in cool air outlet and psychrometer (combination dry/wet bulb thermometer) near to evaporator inlet.
5. Check that high pressure gauge reading is within specified range as outlined under ``System Diagnosis.'' If high pressure gauge reading is above specified range, pour water on condenser until specified range is reached. If gauge reading is below specified range, cover condenser front surface area.
6. Making sure that dry bulb portion of psychrometer is 77 to 95°F, operate system until all gauges and thermometers have stabilized.
7. Compare temperatures of dry and wet bulb portions of psychrometer, then +determine relative humidity using graph, Fig. 2. Record reading.
8. Measure the difference in dry bulb temperatures at cool air outlet and evaporator inlet. Record reading.
9. Using information gathered in steps 8 and 9, determine if system is operating properly by using graph, Fig. 3. Intersection of the two points should be within the diagonal lines as shown.