In the peak of an Australian summer, air conditioning is not an option but a vital consideration. Without car air conditioning, you'll find it difficult to survive the commute home at the end of the day. This is every reason for you to keep an eye on its efficiency to spot any early warning signs of trouble. To be ready for every eventuality, it helps to understand how the system works in the average vehicle. While there are a number of individual components involved, the main features are the evaporator and the condenser. What are these and how do you know if they are okay?
Evaporating Begins the Circle
Both the evaporator and the condenser look on the outside like miniature radiators. The evaporator is the heat exchange mechanism, and it is fitted with a series of tubes laid out in a lattice fashion. A special refrigerant passes through each tube, and as it does so, warm air from the vehicle passes across the surface and is transferred to the refrigerant. The humidity within will then condense on the outward surface and will be evacuated through a tube to the outside of the car.
Condensing Completes the Circle
In a vaporous state, the refrigerant will then pass into the condenser. Once again, this is configured in the same way as a small radiator, but this component is exposed to the outside air. Cooling air will have the reverse effect on the vapour and will convert it back into a high-pressure liquid in order to complete the circle.
Each of these major components can encounter problems as time goes by. For example, the evaporator may 'freeze' when the temperature is improperly regulated, and this will divert air to the outside rather than through the cooling fins. You will notice a reduced performance level until the evaporator is flushed out or otherwise cleaned and may also have to replace the blower motor or cabin filter at the same time.
The condenser may also be subject to restriction or difficulties with airflow across its surface. You may also face problems with the cooling fan or its clutch, and in every case, performance will be reduced or the unit may fail altogether.
How to Fix
If you take your vehicle into a mechanic for a regular service appointment, then they will often be able to head off some of these problems before they become acute. Typically, a major service will help to flush or clean out the condenser or evaporator. However, don't leave it too long, as it may sustain internal damage and require replacement.