Anyone done an A/C conversion from r12 to r134 in a vehicle?

I've been reading up on it, but a lot of the info doesn't make sense.

Some websites say all you do is change the fittings and flush the system and add a newer freon that will mix and be ok with any residual r12

Other sites say that the condenser and some other pieces have to be swapped out.

Or would it be easier to just find someone with the proper tools to recharge with r12?

We had a pickup we had converted from R12 to R134 several years ago.

From memory the R134 requires a larger volume of Freon to achieve the same cooling capacity, so one alteration to the system when converting to R134 was increasing the system capacity. Other than that you past things I know.

I had it done on one older vehicle, didn't do it myself. I don't remember exact pricing, but it was cheap enough for me to not go through the hassle myself.

I am not an auto a.c. guy, but I have been around long enough to have work with R12.

Old R12 compressors were lubricated with mineral oil. R134A is not compatible with mineral oil.

The seals must be upgraded to green seals to prevent leaks. Here the old seals will have contaminated with mineral oil. Also the R134 molecule is smaller than R12 so leaks are more prevent.

Re condenser.. Parallel pass condenser are common through out the industry. They just work better.

One more thing I noticed, was air flow inside. I had an 88 E150 with R12. When I went to a 96 E250 with R134, on high speed, the air discharge from dash was much greater than the R12 system. So, air flow may be a concern.

The problem with recharging w R12 is finding R12. I have been using substitutes in end of the world for many years. There maybe a good auto sub as well.

Last but not least, there is a company in Fort Worth the sells after market systems for classic cars. Old air products.

A lot depends on your budget.

I actually have r12. I just don't have experience with r12.

Nor do I have the manifold set to charge the system

gauges are still common and they are cheap in the pawn
shops. the main problem in getting it evacuated properly
whether you use R-12 or R-134A. i have both gauges but no
vacuum pump.

Flush out the old oil, change the seals, change the accumulator I think is all. You may have to change the expansion valve to a larger size if not cooling as good as R12.

If it is an older R12 system or a converted to 134A - get some R12A. Just don't be smoking while installing it.

I have actual r12.

I don't have gauges

It hasn't been touched yet, still an r12 system

Although not ideal, simply removing the R12 (the difficult part), evacuating and recharging with R134/PAG oil works just fine in 99% of applications. Dual purpose 12/134 machines still in operation are nearly impossible to find I'd bet.

Yes, the volume is different.....

(r12*0.9) + .25 = R134

Or otherwise stated.....take 90% the spec R12 charge and add 1/4 lb to that.

If you have not done it yet send me a PM.