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Performance Test

Cooling Performance Test, A/C System
A performance test shows whether the A/C system is actually working. There may still be faults in the control of the A/C system or the temperature in the cabin, which require more thorough investigation.

Conditions:
Doors and windows closed
Panel vents all open
Engine speed 1500 - 2000 rpm

Control Settings Manual A/C:
Fan speed 4
Temperature cold
Air distribution valve VENT
Recirculation yes

Control Settings ACC:
Fan speed Max. fan
Temperature LO
Air distribution valve "VENT" manual selection
Recirculation yes

Readings After 5 Minutes at ambient temperature 20 and 30 °C
Air temperature measured approx. 100 mm inside
the centre facia vents 6 - 10 °C

Pressure measured on suction side of compressor,
compressor switched ON/OFF 1 - 3 bar

Pressure measured on pressure side of compressor,
radiator fan ON/OFF
R134a 16.5/12.5 bar

Readings After 5 Minutes at ambient temperature 40 °C
Air temperature measured approx. 100 mm inside
the centre facia vents 10 - 12 °C

Pressure measured on suction side of compressor,
compressor switched ON/OFF 1 - 3 bar

Pressure measured on pressure side of compressor,
radiator fan ON/OFF
R134a 16.5/12.5 bar

Radiator fan second stage
ON/OFF 22/18 bar