System Performance Test

R-134a systems require the use of special service equipment designed specifically for R-134a systems. R-12 servicing equipment cannot be used on R-134a systems.

1. Connect manifold gauge set to system.
2. Start and run engine at 2000 RPM, then turn A/C system On.
3. Set temperature control to MAX and blower motor to III.
4. Wait until air conditioning system stabilizes, then check readings at high and low pressure gauges.
5. Normal reading for high pressure gauge should be 171-235 psi. Normal reading for low pressure gauge should be 21-23 psi.
6. If pressure is not within specifications, record stabilized pressure and perform necessary system diagnosis.