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Air Conditioning Questions?

YOUR CARS AIR CONDITIONING

It’s a hot sweaty day and the trade winds have stopped. Instead of offering a cool arctic relief your A/C system is melting your face off.  What to do?

THE DIAGNOSIS

The first thing step is to get a diagnosis. Your cars A/C system is a little complicated but most problems can be put into one of three groups:

  1. A mechanical failure
  2. An electronic failure
  3. A leak

The first thing the mechanic will do is look for any obvious mechanical failures. These can include a broken belt, a seized compressor or compressor clutch etc.

Then they will check for any obvious electronic failures, including broken wires and computer codes.

The third thing they will do is make sure that the system has enough refrigerant in it.  It is very common to find that it has leaked out.

The refrigerant currently used in most cars today is called R-134a. It is a clear colorless gas which makes it difficult to pinpoint the source of the leak.  To find the leak, the system will be charged with R-134a and a fluorescent dye.  The dye leaves a telltale sign as it leaks out that can be identified in the future. An added benefit of charging the system is in aiding the diagnosis. The AC system uses at least one pressure switch to turn the system on and off. If the system is properly charge but still does not turn on it is a sure sign that there are other issues.

Looking for a quick DIY fix? Small cans of R134a can be purchased from auto part stores like NAPA.   These may bring your AC back to cold quickly. Or not.   A cold A/C system must be dry and free of air. One of the limiting factors of DIY cans is that they do not remove air moisture from the system. Also, your AC system is engineered to run on a specific weight of refrigerant. With a can you can estimate the amount of refrigerant added using a pressure gauge but it is difficult to add the recommend weight required.

Diagnosis Cost: Be prepared to pay between $100 – $200 for an

THE REPAIR

Now you have the diagnosis how much will it cost and what are you getting?

Here are some common A/C repairs and a very general price guide. Prices, of course, can vary wildly depending on the year make and model of the vehicle. It is also important to remember that an A/C system charge needs to be done in addition to most A/C repairs.

A/C charge with dye: $150-250

Note: R134a refrigerant in dispensed by weight. For example, a small compact car will take less than a van with rear A/C. This needs to be performed with almost every A/C repair.

Remove and replace A/C pressure line: $250-600

Note: The pressure hose/lines carry the refrigerant between components.  There are multiple hoses on most cars, including both high and low pressure lines. It is common for them to develop leaks over time.

PIC OF PRESSURE LINE

Remove and replace A/C condenser: $400-800

Note: The A/C condenser looks very much like your cars radiator and is usually located in the same place, at the front of your car.  The condenser cool the refrigerant and helps change it from a gas to a liquid. This is another common place to develop leaks.

PIC OF CONDENSOR

 

Remove and replace A/C compressor: $600-2500

Note: Like the name suggests the compressor compresses the refrigerant creating a high and low pressure differential within the system.  The cost of the compressor itself can vary widely as well as the labor to install it.  When a compressor fails it is common to do a full A/C flush and replace other components at the same time, including the expansion valve and drier. Compressor manufacturers often require these components to be replaced or they will not warranty their parts.  The reasoning behind this is due to what is commonly called “black death”, a sludge that comes from the compressor when it fails. This sludge get spread through system and can cause new parts to fail again.

PIC of COMPRESSOR

PIC OF BLACK DEATH

Remove and replace A/C evaporator core: $800-2500

Note: The evaporator core or “evap” core is usually located under inside dashboard of car on the passenger side. This little part is usually not much more than $150 but the labor is expensive due to the fact that most cars require the removal of the entire interior dashboard up to and including the steering wheel.

PIC IF EVAP CORE

 

THE CRISP COLD AIR

Now roll up the window, crank up the A/C and enjoy!