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A/C - Nominal System Pressures R12/R134A

Group 64
Heating and
Air Conditioning

Bulletin Number
64 13 92 (3646)

Woodcliff Lake, NJ
October 1992
Product Engineering

SUBJECT:
Nominal Air Conditioning System Pressures R-12/R-134a

MODELS:
All





Situation:
The chart has been provided to assist the technician in determining the operational status of a BMW vehicle with a suspected air conditioning problem. The chart provides "nominal" values that approximate typical high side pressure, low side pressure, and center vent discharge temperature for a given ambient temperature, humidity, and refrigerant type.

Note that the pressures given are directly dependent on the amount of refrigerant charge in the air conditioning system. If wide variation exists between the measured pressure values and those given on the chart, the technician should consider an overcharge/undercharge situation as a possible cause.

Warranty Status:
Information only.

THIS INFORMATION IS CURRENT AND SUPERSEDES ALL OTHER SERVICE INFORMATION ON PRESSURE/TEMPERATURE/HUMIDITY RELATIONSHIPS FOR A/C SYSTEMS AS WELL AS ANY OTHER SOURCE OF SIMILAR INFORMATION.