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R-12 System

1. Connect gauge and manifold set.
2. Open at least 1 front window and all dash air outlets, and insert thermometer into center air outlet.
3. Place temperature selector in COLD position, depress VENT button, turn on ignition and set blower to run at high speed.
4. Record ambient temperature, start engine and set to run at fast idle.
5. Depress MAX A/C button, and note discharge temperature after 1 minute. Air discharge temperature should be at least 15°F less than ambient temperature recorded in step 4.
6. Allow system to operate for approximately 10 minutes and note gauge readings.
7. Low (suction) side readings for relative ambient temperatures should be as follows:
a. 59°F, 16-27 psi.
b. 68°F, 21-32 psi.
c. 77°F, 23-35 psi.
d. 86°F, 29-40 psi.
e. 95°F, 36-50 psi.
8. High (discharge) side readings for relative ambient temperatures should be as follows:
a. 59°F, 130-159 psi.
b. 68°F, 162-190 psi.
c. 77°F, 192-224 psi.
d. 86°F, 226-258 psi.
e. 95°F, 275-310 psi.
9. If discharge temperature does not drop by at least 15°F, and/or if system pressures are not as specified, check air distribution system as outlined and refer to ``Heating and Air Conditioning/Testing and Inspection/Procedures.''