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R-134A Systems

SYSTEM PERFORMANCE TEST

1. Run engine at 1500 RPM.
2. Ensure A/C switch is at the On position and the blower motor is at the High position.
3. Set temperature control lever to the Max Cold position.
4. Connect manifold gauge. Low pressure hose is connected to Suction side and high pressure hose is connected to Discharge side.
5. Normal low pressure should be 18.5-28.4 psi.
6. Normal high pressure should be 213.3-241.7 psi.

Fig. 1 R-134a System Diagnosis (Part 1 Of 2):




Fig. 1 R-134a System Diagnosis (Part 2 Of 2):





7. If pressure readings are not as specified, refer to Fig. 2 for diagnosis.