Automotive air conditioning repairs can be some of the most expensive problems that car owners will have to deal with. The worst-case scenario of an internal compressor failure that has spread chips of metal throughout the system can cost thousands of dollars to repair properly on some models.
On the other end of the spectrum, a simple O-ring failure that has leaked out the vehicles Freon should only cost a couple of hundred dollars, if that. The symptoms for both the best and worst case scenario are basically the same to the driver. This is the driver turns on the air conditioning and only warm air blows out of the vents.
This is why I recommend a quick education on how the system works and learning what questions to ask the shop. The article to follow is just my opinion about AC repairs and why you need to be careful when getting this system serviced.
Sometimes my jaded insider point of view can make people in the auto repair business angry because I might suggest that foul play abounds in the business. If you are an honest car mechanic that happens to work in an air conditioning shop that does the right thing then this article does not reference you, so there is no reason to send me flaming e-mails.
In my area of the United States automotive air conditioning has become a big business. Motorists use the system nine months out of the year in south Florida. Many specialized repair shops have sprung up to capitalize on the abundant amount of air-conditioning jobs available.
I have run across shops using extreme heat and humidity as leverage against car owners. No matter what the situation is or how hot it's outside, you have the right to ask questions and see the failed parts. If they say you need a compressor replacement ask them what's wrong with it. Ask if any Freon is still in the system.
If the answer is the Freon has leaked out
then a test charge should have been installed to properly diagnose a
failed compressor. If the answer is yes there is still Freon present in
the system, then ask the shop if they connected gauges and what the pressure readings where.
Getting specific about the pressure readings on the low and high sides is key in determining failed components. Low side pressure should be around 35 to 45 psi with the compressor engaged.
The high side pressure will vary with the outside temperature and the kind of system installed on the vehicle but regardless it should have readings of over 150 psi with the compressor engaged.
If a compressor fails internally but engages a common symptom is lots of noise. Worst-case scenario of a compressor failure is certainly a possibility. In fact this is one component that experiences a lot of stress. So how long will an AC compressor last? An estimate and my opinion based on experience is car air conditioning compressors last about 100,000 miles more or less.
I have another article on this site that you can view about what I consider to be the most common car air conditioning repairs. After turning wrenches for more than 25 years what I see most often is that the Freon will leak out of the system until the pressure gets so low that the compressor will not kick on.
There are a lot of sealing O-rings and threaded connections in an automotive air conditioning application. These can loosen up and start to move over time, wearing away at the rubber O-rings. The system does not hold that much total Freon and even a small leak will cause the system to be inoperative after a while. All too often automotive consumers are approached by a repair shop representative with a number or cost of the repairs.
The shop is looking to keep it simple and may be prompting you for a yes or no answer. This is when we need to start asking questions. Answers to your automotive questions that don’t seem to make sense or raise doubt should be researched.
When in doubt take the vehicle to another location for a second opinion. I recommended you do not inform the second shop of the first repair centers diagnosis.
I have written a lot of Diy information about this system on my other website that is geared towards driveway mechanics. These are articles that you can read to gain more knowledge about how car air conditioning works.
If you are interested in reading more articles about the automotive business this next link will take you back to the automotive news section.
you would like to discover what this site is all about and the
information you can find here this next link will take you back to the
homepage where you can find out how to ask car questions.
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