It is pretty hard to buy a vehicle without air conditioning these days. Once you have had air conditioning it is hard to give it up. When your air conditioning first breaks down you will consider living without it. Not …. when it has been a summer like this one though.
Like many systems of the automobile air conditioning systems have been invaded with electronics but basically the function and various components are the same as the original.
A compressor, evaporator, condenser, refrigerant metering device and the various connecting hoses and pipes are common to every system. The most frequent failure has always been the same. The refrigerant finds a way to leak out. Once the refrigerant level gets too low the passengers and driver get hot and bothered.
Low refrigerant is not the only failure though. There are many possibilities. Electronics and electricity are involved. The systems are a lot less primitive than the originals. As with most systems several computers will have some say in how and when the air conditioning operates.
Therefore when you phone your mechanic in a hot and bothered state to ask, “how much” the answer will be “it depends.”
A broken wire can take down an air conditioning system as well as a corroded evaporator. The broken wire may be quickly fixed and you will be on your cool way.
A corroded evaporator that was one of the first parts installed in your vehicle when it was put together on the assembly line may present another scenario all together.
Evaporator removal and replacement on some vehicles can be a 10-hour job. Complete disassembly and removal of the seats, centre console, and dashboard requires a patient, careful, methodical technician. Then the intricacies of the air distribution system must be disassembled to get at that elusive part.
As with all systems automotive care and maintenance can reduce the incidence of air conditioning system failure. The condenser is located in front of the radiator. It is a bug collector.
Cleaning off those bugs not only helps to cool your engine it also makes life easier for your air conditioning system.
Another oft-neglected maintenance practice is cleaning the air intake at the base of your vehicle’s windshield. Those leaves, buds, seeds, needles that accumulate at the base of your windshield can sneak their way down into the air intake passage to the blower fan and then air conditioning evaporator. While functioning the evaporator becomes wet with condensation. The leaves and needles mix with the condensate forming a somewhat acidic mash. This stuff can be corrosive to the evaporator (it is made of aluminum) along with blocking it up. This reduces the cooling performance and eventually leads to failure as the evaporator corrodes through and lets the refrigerant out.
By design with time the refrigerant becomes low in all air conditioning systems. Compressor seals, rubber hoses, “O” rings and gaskets are not perfect barriers to the refrigerant.
If you are cognizant of somewhat reduced cooling from your AC system it is a good idea to have it serviced before it does not work at all. An evacuation of remaining refrigerant followed by a deep vacuum and complete refrigerant recharge will help to increase the service life of the system.
The proper amount of refrigerant helps to better circulate the oil to the compressor. The deep vacuum aids in removing internal moisture from the system that will prevent corrosion from the inside out.
A little maintenance can go along way to ensuring a cool summer.
Trail’s Ron Nutini is a licensed automotive technician and graduate of mechanical engineering from UBC. E-mail: nutechauto@telus.net