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HVAC
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Whenever the engine is operating, the pulley is rotat-
ing since it is connected to the crankshaft by a belt,
but the compressor does not operate until the clutch
is energized. When the air conditioning system is
switched ON, the ECU generates a signal for ener-
gizing the compressor. The electromagnet attracts
the pressure plate and pulls the plate against the
friction facings on the pulley. The friction between
the facing and plate causes the clutch assembly to
rotate as a unit, and drive the compressor.
9. CONDENSER
The condenser is a heat exchanger used to cool the
hot vapourised refrigerant. Also the refrigerant
changes its state from vapour to liquid. The conden-
ser in this vehicle, as in many other vehicles is
placed in front of the radiator. A condenser fan is
provided to force the air in to the condenser to cool
the refrigerant inside the core.
10. RECEIVER DRIER (R.D)
It’s a storage device for liquid refrigerant and has
three main functions.
i) It absorbs the moisture in the refrigerant.
ii) It allows only liquid (
high pressure liquid)
to pass
through to the TXV.
iii) It keeps a reserve of refrigerant to accommodate
fluctuating refrigerant requirements.