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Testing The Performance Of The Climate Control System






Testing the performance of the climate control system





Performance test
The performance test provides an indication of the capacity of the air conditioning system. During the test, the temperature of the air flowing out of the center dashboard vents is measured under predetermined conditions (engine speed (RPM), fan speed, control settings etc).
If the capacity is too low, this may be due to a number of "external" reasons, for example:
- a slipping drive belt for the compressor
- insufficient air flow to the condenser (blocked by insects / dirt, foreign objects)
- poor engine cooling fan (FC) function
- insufficient air flow to the climate control system (duct blocked by leaves etc)
- poor blower fan function
- incorrectly adjusted control / damper / water valve for airflow - recirculation - temperature.
Too low capacity can also be caused by "inner" causes (faults in the system).
Initially this is checked by:
- visual inspection (damage, leakage. In the event of leakage there is often excess oil = greasy surface)
- listening (there is always a little noise in the system when the refrigerant changes between gas and water form at different pressures)
- feeling the components (if there is cold / warm air, how cold / hot they are)
- measuring the pressure in the system (if possible, measurements should be taken on both the low and high pressure sides).