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Bottled refrigerant, how bad is it?

The AC compressor in my 1993 Toyota Pickup leaks so I get no cool air. My mechanic said not to use the re-charging refrigerant that I see in the automotive sections of the store. But why not? He wont’ say. But if the compressor is shot anyway, what’s wrong with charging it just for a desert road trip?

other then he would have to evacuate the system before he can begain doing the repair. does the shop have a recover machine?

The refrigerant in the stores ought to be identical to what your mechanic uses. Clearly he does not want you to avoid a shop repair. For a one-time repair, go ahead and try a DIY recharge.

There are lots of refill cans on the shelves of these stores with stop leak and odd chemicals that claim to boost the cooling effect of the refrigerant. Any stop leak added to an A/C system can damage a very expensive recovery machine. This is probably why he would not like to see you use it.

If the compressor is leaking from a shaft seal, you’ll need to replace the entire compressor. If it is the recharge plate, the gasket can be replaced much cheaper. If it is the valve at the recharge plate, the valve core can be switched out for a new one without evacuating the system, and be done quickly and cheapest. Do you know how it is leaking?

The AC system in your vehicle uses the R12 refrigerant not the R134a refrigerant that you see in the parts stores. So if you charge the system with the R134a refrigerant the mineral oil in the R12 system that you have won’t mix with the R134a refrigerant. This will cause further damage to the AC system. Then if you decide to have the AC system serviced at a later date and there’s a cross-contamination of oils/refrigerant it’ll cost a lot more to repair.

Either repair the AC system so it still uses the R12 refrigerant, or have the entire system converted over to the R134a refrigerant.

Tester

My preference is not to see novices working on air-conditioning systems. If you don’t know what you’re doing, you can easily damage the system or injure yourself (especially your eyeballs).

Roadwalker: By now most R-12 systems have been converted over to operate on R-134a refrigerant. Take a look at your service ports on the A/C lines and see if they have conversion fittings attached and a tag telling the date the conversion was done…

Let us know what type of refrigerant your system is charged with and we can offer better replies…

Assuming your system us A) R-134 and not R-12 and B) still has some charge left and has not lost 100% of it’s charge the stuff at the store works great. I have been using it for years no issues. The reason it is so important that your system has not lost all of it’s charge is that if it has, atmosphere has leaked in. This means moisture. All AC shops will pull a vacuum on any system that has been opened to the atmosphere. This removes any moisture left in the system and most of the contaminants in the air.

It seems that the vast majority of the DIY refrigerant is blown off in the parking lots of the stores where it is sold. Lucky for most, the current crop of DIY chargers uses an easily blown out plastic hose. Years ago the R-12 cans became hand grenades when the wrong service port was connected or when the compressor shut off with a full charge and the low side quickly jumped past 100 psi. Shops want no part of the mayhem that can result from bungling the job or the problems of cleaning up the mess that often results.

I also use freon bought in auto parts or department stores. As long as you don’t get the freon with leak sealer or leak detecting dye in it it’s the same thing you get when buying it in bulk. The freon without leak sealer or leak detecting dye is also cheaper.