Before we go too far, this is not about the latest car models; just how to have a cool car. It is that time of year again, though it took a while, the heat is on and the air conditioning system in your car will be working overtime. Just how does this work and what can you do to keep things cool? There are many parts of newer a/c systems, electrical and mechanical. Many areas that refrigerant can leak, which we will call Freon for short. We will cover the basics this time around.
The a/c system revolves around pressurizing a gas (Freon) which causes the Freon to cool. The Freon then circulates to a radiator like evaporator core where the fan blows air across it to create cool air in your car. This is a very simple explanation and there are many other components involved.
Obviously, if the car is not providing cool air then there is a problem. What is wrong is the next question. In most cases you should begin with an evacuation and recharge of the complete system. This enables the tech to know that the levels of Freon and oil are proper, plus that pressures are within limits. Dye is also added to search for leaks-some which may turn up later. Leaks are the most common problem and can be expensive to repair, although some are not so bad. There can be 6 or more connections that can leak plus various components. Leaks do not allow proper pressure to build and low Freon level does not provide cooling. Like any other fluid or gas system one leak can prevent you from finding others, so be aware that other leaks or problems may be present. You must take it step by step.
A common problem is the compressor, the heart of the system. It can leak, seize, come apart or just quit working. This leads to expensive repairs typically. Other parts recommended to be replaced at the same time are the accumulator and orifice or expansion valve. These act like filters collecting debris and moisture. The compressor is driven by a belt and is what pressurizes the Freon and circulates it.
One other problem seen in some newer cars is a clogged cabin air filter. This acts like the furnace filter in a house and can easily clog with dirt, hair, pollen and other airborne particles. Air flow can be drastically restricted and stinky too. This is easily fixed with filter replacement.
As stated, this is just a quick look at an a/c system. There is so much more in today’s systems that it would take pages to cover. Just be sure you have your car’s system check annually, hopefully before there is a problem.