Air Conditioners, including those fitted in your automobile, are designed to remove unwanted ‘heat’ from inside, dehumidify the cabin atmosphere and supply cool air for the comfort of the occupants. Every air conditioning system works by taking the heat from the cabin air to heat and evaporate the refrigerant liquid.

The liquid refirgerant is pressurized by the compressor, and travels to the Thermal expansion valve which regulates the pressure allowing the gas to evaporate. In the process the refrigerant absorbs the heat in the evaporator core. By now it is clear that the most important component is the compressor.

Think of it like the your heart, and the refrigerant is your blood. The compressor is the pump that circulates refrigerant around the ac system. Initially, cold refrigerant is passed through metal tubing to the dash area in your car to the ‘evaporator zone’.

This where the heat is removed.  It has an ‘evaporator core’ resembling a miniature radiator with thin tubes and metal fins. The difference is that, unlike the radiator, the air conditioner’s evaporator has no coolant or anti-freeze . . .  and the evaporator  is cold whereas the radiator is hot.

A small dash-controlled fan or blower is fitted behind the evaporator. It blows the air through the evaporator core and into your cabin. The refrigerant absorbs the heat from the cabin with the help of the ‘condenser’ fitted in the front of the car.

Refrigerant circulating back from the cabin carries the heat through rubber and metal tubes to the condenser which contains allows the heat to be absorbed by the surrounding air. It is then forced through fine slits while a cooling fan removes the heat. The cycle is repeated continuously so that the atmosphere in the cabin remains cool.

After having been familiarized with how your automotive air conditioner works and what its major components are, it is interesting to see common things which can go wrong, and how to remedy them.

Four of the most common of such problems include:

• Low or total lack of air flow across the condenser -  this could be due to problems with the electric cooling fan or viscous hub. Check to see if this is turning (in models with fan blades visible). If you aren’t sure, call a qualified and professional automotive air conditioning firm like Stokes and Renk
• Low refrigerant level – this could be suspected if the cooling efficiency is low, for example even with the car AC fully ON there is very little cooling inside. This problem can only be rectified by a certified automotive air conditioning service provider such as Stokes and Renk.
• AC compressor is operating, but cooling is poor and the engine is overheating – this happens in models that have fuel injection. The engine ECU sees a overheating situation and then stops operation of the airconditioning system to protect the engine. If the engine is overheating, reach for the phone and call Stokes and Renk, before even more serious problems develop with the car.
• If the air conditioner does not start at all, check and confirm the fuse is not blown or that the switch hasn’t accidentally been disconnected while cleaning etc. Fuse locations can often be found in the owners manual. Electrical connections can be often the culprit, which can be identified with a little experience.

If your car needs a complete change or replacement of major components such as a  compressor, your only course of action is to engage true professionals like the team at Stokes and Renk.

Bare in mind that the refrigerant in older models is R-12, a substance known for its adverse impact on the environment (it contributes to ozone layer depletion). Modern vehicles use R134A refrigerant gas which although does not deplete the ozone layer, is still harmfull to release into the atmosphere. The minute you suspect there is anything with your vehicles air conditioning system call Stokes and Renk.

In short, automotive air conditioning units have very few ‘user serviceable’ parts or components. They require the assistance of a qualified and certified mechanic.  Whenever low refrigerant level is suspected or low cooling is felt, do not hesitate to seek professional help from the qualified personnel at Stokes and Renk.