A/C leak detection question

Why would you want to switch back? R12 isn't getting any easier or cheaper to find. Just make the change to 134A and be done with it.

 

A good electronic leak detector will work with either R12 or 134a and it should be able to find even the smallest leak. It is a matter of choice, but I still keep R12 cars on R12 if possible. I have two reclaimer machines and I use the one with the re-cycled R12 to leak check systems. When the system is "tight" and working, I evacuate and re-charge with "virgin" freon.

So far, I have not had trouble getting R12, but to be sure, it is more expensive. Still to charge a single car it is about $70 to $90, which isn't all that bad.

The advice in the post above is good. If you do the work to change over, it it is hard to make a case for changing back. I don't think that the system performance difference is all that great, although I have not done any meaningful testing.

 

R134a is a less efficient refrigerant than R12 (Freon), so unless you intend to change some of your components to higher capacity, more efficient modern ones designed to work with R134, you are better off to stick with Freon. Most shops have the equipment to work with Freon without leaking fluorocarbons, so it is not a big deal one way or the other.

Taz
Terry Phillips

 

The O-Rings for R-12 are not compatible with R-134a systems and the labor associated with changing all the O-rings over to an R-134a system is one of the biggest contributors to cost of converting a system.

If you need a brand new, York A/C compressor that is compatible with R-12, R-134a, R-22, etc I have an extra one left over from a dual project for $348 plus s&h. Manufacture date of June 2009, never mounted, only removed from the box for inspection and has a 40% higher cfm than the original yet has the same universal mount.

 

I had a leak in my 330 and the system was completely empty. The A/C guy just released the R12 that was in his hoses (an ounce or so) that connected to the gauges. That was sufficient for his sniffer to find the leak. No need for a full load with leak detection dye. Just find a good A/C tech.

 

Good news! Glad to hear that you are "getting warmer" so that you will soon be getting cooler. An electronic leak detector should have a "lock out" feature that will reject readings less than or equal to the previous high reading. This allows one to home in on a leak even in an area with a background concentration of freon.

 

I would just take the compressor back to where you bought it for a replacement. You can also ask for the cost of the lost R12, but don't hold your breath.

 

A few questions mate...

Did you fit the compressor yourself?

WHY, did you replace the compressor in the first place?

Just curious.

 

Cool man.

Sounds like he may have pinched an oring when putting the a/c hoses onto the new compressor?

If the leak is THAT big, then it should be able to be found using the sniffer test.

Apparently a/c systems that leak overnight are HUGE leaks in the a/c world.

Either uses the sniff test or the dye, let him do his thing. I hope HE is paying for the gas.

Does this guy know what he is doing?

He can use just bottle pressure (little gas used) of R12 or R134A to look for leaks with the sniffer or the dye. If he has no luck, then charge the system up to full pressure to look for the leak. Then, when you find the leak have him recover the gas immediately. That stops it being wasted while he fixes the leak.

You can also use nitrogen to pressurize the system and check for leaks with the sniffer or dye. Any method can be used, just as long as he knows what he is doing.

My guess would be a leaking/damaged oring when hoses were put back onto new compressor. Or, the actual hose on the compressor leaking due to the mechanic "upsetting" the hose by bending it out of the way when he removed the old compressor.

Either way, he should warrant his repair. Good luck with it mate, let us know how you get on.

 

Yes, the "lock out" feature of an electronic leak detector is very handy. It lets the unit ignore the concentration of the freon cloud in the vicinity and home in on the higher concentration of the source of the leak. It is almost never necessary to fully charge a system to find the leak. Often just a few ounces of freon is all that it takes. Start with the most likely places to leak: the shaft seal, the roto-lock seal on the compressor head, and the hose fittings. It is going to be unlikely that the compressor is leaking from the case joints. Also look carefully at the hoses where they leave the compressor and pass over the gas tank and disappear down into the chassis. There are many sharp edges and things that protrude that can wear through the hose itself as the engine moves around and vibrates. It is possible that the leak is not a compressor issue at all. Sometimes a big leak can be found with just a little soapy water painted around a suspected area. Sometimes a big leak can be found with just the vacuum pump and listening with a stethoscope or brushing on some refrigeration oil on a suspect joint and looking for the oil being drawn in.

Happy hunting!!