Car Air Conditioning



Car air conditioning systems cool the vehicle and its occupants in hot weather, and are now a common feature in most modern cars. Car air conditioners use significant power; although in comparison the drag of a car with closed windows is less than if the windows are open. There is a constant debate on the effect of air conditioning on the fuel efficiency of a vehicle. Factors which are taken into account when looking at fuel mileage are wind resistance, aerodynamics and engine power and weight. Other factors on the impact on the engine and an overall engine heat increase can have an impact on the air con in the car.

1. What are the benefits of air conditioning?

The benefits of having air conditioning is that it provides efficient cool air in the summer and in the winter it provides warm dehumidified air, which easily demists steamed up car windows.

Air conditioning filters pollutants and airborne particles which keeps the air in your car clean and can also help with drivers and passengers who have allergies. Finally, air conditioning in your car can provide a pleasant and odour free environment at all times.

2. What causes the smell in my air conditioning system?

The air conditioning smell is caused by fungus, bacteria and other microbes growing inside the evaporator core. The moist environment can be very conducive to the growth of these organisms. As car manufacturers are continuing to downsize all their components to save on space and weight, the problem of growing organisms has been increased. While car manufacturers have made the evaporator more efficient, it has also made it more prone to trap moisture, which contributes to the growth of organisms such as fungus and bacteria.

3. Does my air conditioning use more petrol?

The answer to this is ‘yes’ it does, but not as much as your may think. But then think of the alternatives to using your air conditioning in your car. You could open the windows but that would increase the wind resistance and can add up to 10% to your fuel consumption, especially for example on the motorway. As well as the increase in wind resistance, having your windows open creates extra noise and pollution. Also, it’s worth pointing out that air conditioning in your car should be run at least once a week, especially in winter as the seals of the seals within the air conditioning system can dry up and shrink, potentially costing you more in future in new parts and repair.

4. Why does my car need an air conditioning recharge?

Your car air conditioning system can lose up to 15% of it’s refrigerant every year, so for example a three year old car may have lost almost half of it’s air conditioning refrigerant, which can seriously impacting on the performance of the system and damaging the components involved in an air conditioning unit. You should also regularly have your car air conditioning system serviced to reduce wear and tear on each of the components and help avoid potentially big repair bills.

5. Why should I get my air conditioning serviced?

As we have previously mentioned, through not using your air conditioning the seals can dry up. When car manufacturers service your car they only test to see if the air conditioning works, not that all the components are in full working condition. Regular air conditioning system servicing ensures the system is full of refrigerant, that their are no leaks, the pressures are correct within the system and that the hoses, seals and pipes are all in full working order.

6. What’s the best way to run my air conditioning?

Turn the air conditioning on, ensuring that it’s not set to ‘economy’ mode. When you first get into your hot car, open the windows and ensure that the air vents are set to face level. Remember cold air falls and hot air rises. Turn the temperature to as low as it will go, and the blower as high as possible. When the temperature becomes more comfortable, close the windows and increase the temperature of your air conditioning to a more suitable level as well as decreasing the blower speed. You should also point the air vents upwards to ensuring the cold air flows down again.