The air conditioning system in your car is comprised of a compressor, condenser, expansion valve
and evaporator. If you have ever used a can of compressed air to clean computer components, you
will know that the bottle gets very cold in a short amount of time. This is due to the rapid expansion
of the compressed gas. The same thing happens in your car’s air conditioning system. Refrigerant
(AKA Freon) is compressed in the compressor and turns into a hot gas. In the condenser, this hot
gas is cooled to a liquid state and travels to the expansion valve. As the Freon goes through the
expansion valve it returns to a low-pressure gas and rapidly cools in the evaporator. A fan blows
over the evaporator and cools the air that eventually blows out your vents.
◦From time to time the A/C system needs to be recharged to bring it back up to maximum efficiency.
Sometimes a leak may cause loss of refrigerant and will need to be fixed before refilling. It's difficult
to tell if a leak is present without specific test equipment so let it up to a professional.
◦In recent years, the EPA has phased out the use of R-12 Freon in all refrigeration systems and R-
134 has become the new standard. If you have an older system with R-12 you may need to retrofit
your system to handle the new R-134 refrigerant. Sometimes seals, hoses and even the
compressor need to be changed. The problem arises when the older seals and hoses are not
compatible with the new oils found in the R-134.
◦Corrosion will cause the heater core (secondary radiator) to leak. This will manifest itself by leaving
steam into the passenger compartment and fogging your windows. You will know there is a leak by
the sweet smell coming from your vents. Unfortunately changing the heater core is usually not the
easier job in the world as engineers tend to squeeze them into some pretty tight spaces under the