Air conditioning Retrofits
by Jim Kerr

The cost of keeping cool in Canada is rising, but not as fast as in the United States. I am referring of course to the cost of having work done on your vehicle's or equipment's air conditioning system. Part of this cost increase has been due to price changes in R-12, the refrigerant used in almost all automotive air conditioning systems until 1994. Here is why.

R-12 refrigerant, often called "Freon" (the trade name registered to the Dupont Corporation) has a limited supply. The Montreal Protocol, an agreement between many industrialized nations, placed an end to production of R-12 on December 31, 1995, in an effort to protect the ozone layer in our atmosphere. After that time, no more could be produced in or imported into the participating countries. What we have now is all we will ever have. The laws of supply and demand begin to take effect.

A typical vehicle will hold between one and two kilograms of refrigerant. Only five years ago it was possible to buy R-12 at just over $2.00 per kilogram. The cost of filling a vehicle was small. Today, the cost of bulk R-12 is over $55.00 per kilogram. By the time the cost of the required machines used to handle this bulk R-12 have been added, the final price to consumers is much higher. The cost of R-12 is now a significant portion of the repair bill!

If you think this is high, you should try having your vehicle repaired in the United States! The Environmental Protection Agency (EPA) in that country has placed a $12.75 US per kilogram tax on R-12. This tax, combined with higher R-12 prices due to increased consumer demand, has caused the price of bulk R-12 there to increase dramatically. Add to this the cost of equipment used to handle it and the price is double of what it costs in Canada!

R-12 will continue to increase in price as the amount available decreases. Currently in the United States, there is an estimated current supply of 80 million to 150 million pounds of R-12. The auto industry will use about 35 million pounds this year alone, and refrigerators and residential air conditioning will use 25 million pounds this year. As you can see, the R-12 currently available may be used up in the next two to three years.

So how do we keep the costs down? The easiest way is to have your vehicle's air conditioning checked for leaks on a regular basis; at least once per year or immediately if the system isn't cooling the interior well. Don't wait until the system completely stops working. The refrigerant leak detectors used by most good repair shops can detect leaks so small that it would take a couple years for the system to empty itself. When a leak this small is found, the R-12 can be removed from the vehicle, the leak repaired before it gets bigger, and the R-12 can be placed back in the system again. This conserves our available R-12, which keeps the cost of the refrigerant at a reasonable level. As a bonus, it also protects our environment.

What can be done when R-12 is no longer available? With careful conservation, R-12 may be available for a few more years, but eventually it will all be gone. Several other refrigerants have been tested but only R-134a refrigerant is currently recommended by any automobile manufacturers. R-134a has been used as an original equipment refrigerant on some 1993 and almost all 1994 and newer passenger cars and trucks. This refrigerant isn't as efficient as R-12 but design changes to air conditioning components have enabled this refrigerant to work well. Other propane and butane blend refrigerants are sold in some parts of the country, but these have been banned in many of the United States and will not be serviced by many repair shops. Replacement compressor manufacturers will not warranty their products if refrigerants other than R12 or R134a are used.

The problem is R-12 and R-134a are not compatible. Each refrigerant uses a different oil in the system. Sludge will form and plug the air conditioning system if R-12 is mixed with the oil for a R-134a system. Converting a system to use R-134a can cost from $50 dollars to several hundred dollars, depending upon what is required. Most conversions are not expensive. The easiest conversions require complete removal of all R-12, installing new style service ports, changing the pressure switches, and refilling the system with R-134a. Removing all the R-12 is the most difficult part. A little remains trapped in the oil inside the system and the vehicle may have to have the air conditioning system evacuated with a vacuum pump for more than an hour instead of the normally required few minutes.

The more costly conversions will require changing the vehicle's compressor, condensor, hoses, and drier units as well as fittings and pressure switches. Each model of vehicle has different requirements and the manufacturers have given recommendations on what components require changing. Most only recommended converting if there has been a major air conditioning system failure but the cost of R12 refrigerant has skyrocketed in the last couple years, while the cost of R134a has dropped dramatically. In almost all cases, it will now be cheaper to convert your system than to buy R12.

Jim Kerr is a master automotive mechanic and teaches automotive technology. He has been writing automotive articles for fifteen years for newspapers and magazines in Canada and the United States, and is a member of the Automotive Journalist's Association of Canada (AJAC).

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