Fabtech Technical Campus Poly. (Shift), Sangola. Presentation on AUTOMOBILE ENGINEERING Chapter no.06 Automobile Air Conditioning System By: Mr.Solage R.D. (Lecturer in Mech. Engg.Dept.)

Chapter no.06 Automobile Air Conditioning System Air conditioning is the process of altering the properties of air (temp.and humidity) to more favorable condition to the human. maintaining the temp. irrespective of the atmospheric condition or simultaneous control of temperature, humidity, purity and air motion.

Necessary Air conditioning is necessary for the automobile for providing comfort and luxurious (comfortable) life. To cool the cabin during summer, keep it warm during winter and remove the humidity from the air inside. The air conditioner for automobile involves, 1.Temperature control. 2.Air circulation control. 3.Humity control. 4.Air purification control.

Consider several factor to achieve the required condition for all seasons Higher outside temperature. Dissipation of heat by engine. Solar radiation through glass, windows and roof depending upon the position of sun and intensity of solar radiation. Vehicle colour. Vehicle speed.

Air Conditioning System

Components of Automobile Air Conditioning 1.Compreesor. 2.Condenser. 3.Receiver and dryer. 4.Expansion valve 5.Evaporator. 6.Blower. 7.Magnetic Clutch Control.

1.Compressor-: -it acts as a human heart which suck vapour refrigerant and increase its pressure and temperature and supply in the system. -It is fitted in the front portion of the engine and driven by ‘V’ belt. It is operated by magnetic clutch when air conditioner is switch ‘ON’. 2.Condenser-: -The condenser is a device used to change the high pressure refrigerant vapour to liquid. -it is mounted in front of the engine radiator ,and it looks very similar to a radiator.

3.Receiver-Dryer-: -This is a small reservoir for the storage of liquid refrigerant ,and removes any moisture if present in the system. -if water is present in the system which can damage the air conditioning system. 4.Expansion Valve- -This expansion valve reduces the pressure and temperature on the refrigerant, so it can move into the evaporator.

5.Evaporator-: -The evaporator is heat absorbing component that looks similar to a car radiator. -it has tubes and fins and is usually mounted inside the passenger compartment below dash board. 6.Blower-: -Fresh air or recirculating air is drawn by blower. it is driven by electric motor.

7.Magnetic clutch control-: -Temperature of car cabin is below/upper set point then magnetic clutch disengage. -Pressure in the system extremely high or extremely low. -Compressor lock up. 8.Control panel-: i) Thermostat-:Temp.setting knob. ii)Speed setting knob

9.Refrigerant-: -The fluid that passes around the whole system is known as refrigerant. -in old day ,R-12,R-22 was the refrigerant used in almost all cars. - But it affect to the depletion of ozone layer as it was a chlorofluorocarbon (CFC). -now day R-134a are used which is eco-friendly to the environment. -R-134a is used in air conditioning because it evaporates and liquefies easily, and has chemically stable, good heat transfer, non flammable, non explosive.

Important Precautions While Using AC System operate the air conditioner at least once a week, internal parts lubricated, blocking chances. do not turn ON A/C as soon as you enter the car.