Calsonic

Fig. 1 Air Conditioning System Performance Chart:

A/C performance changes considerably with changes in surrounding conditions. To check system operation, follow procedure outlined below:

1. Park vehicle indoors or in shade.
2. Open all windows, keeping doors closed.
3. Connect manifold gauge set to system.
4. Set mode switch to A/C MAX position, then air inlet control switch to CIRC.
5. Set temperature lever to COLD position.
6. Start engine and hold speed at 1500 rpm.
7. After A/C has been operating for 10 minutes, measure system pressures.
8. Measure temperatures of inlet air to blower and outlet air at dash panel grilles.
9. Measure temperature and humidity of the ambient air 3.3 feet from front of condenser.
10. Check for problems by comparing test results with standard pressure in performance charts Fig. 1.
11. Pressure will change in the following manner with changes in the conditions:
a. When blower speed is low, discharge pressure will drop.
b. When intake air humidity is low, discharge pressure will drop.
12. Temperature will change in the following manner with changes in conditions:
a. When ambient air temperature is low, outlet air temperature will become low.