r-12 to 134

Topic: r-12 to 134 (Read 1510 times) previous topic - next topic

r-12 to 134

June 01, 2005, 11:46:58 AM

not sure if this is where this goes but here it is. has anyone converted their older bird or cougars to r134 freon. i am using r12 and have to go to mexico to get it recharged every couple of years. the r12 isn't real cold either. i live in arizona so ac is a must somedays. i know there is some type of converstion but not sure what it entails

Re: r-12 to 134

Reply #1 – June 01, 2005, 12:51:41 PM

***NOTE*** The following is not presented as my advice on the matter.. but as I stumbled across this while doing my own research on the issue, I felt it might be interesting to anyone else pondering this.

http://members.aol.com/ellsworthc/cfc/cfc.html

On my '86, I ran for about a year with "Hot Shot" (r414b, I think it's called) put right into my system with no changes to the system and no purge of whatever was already in there. It was getting a little weak this month, so I took it back to the same friend who hooked me up last time.. made him a deal to where I got the recharge for free. He used r134a this time around, again with no purge of the r12 or r414b. (just put an adapter on the old fitting) It's working fine now. Eventually I'll have the system purged and try the condenser swap that was mentioned here.

Re: r-12 to 134

Reply #2 – June 01, 2005, 01:22:31 PM

thanks for the post. im think i am going to try the r134a conversion kit if it is still carried at the local auto parts store. the posts were from 2001 so i hope they still do.

Re: r-12 to 134

Reply #3 – June 01, 2005, 01:28:04 PM

You know where I saw a cheap kit just a few days ago? Target. $30 for the conversion fittings, a hose w/ a cheap gauge on it, and I think a couple cans of 134a. (not sure if it had the ester oil those posts mentioned, tho) If you strike out at the auto parts store, there's always that possibility.

EDIT: I should say that I still hope you're not basing anything solely on what I've posted here, which includes that link. I'm hoping a few more people chime in on this before you commit to a course of action. I realize that my own course of action *could* result in damage to the system or whatever.. but there's not much I can do about it right now. You do what you can with what resources you have. I had a couple things I could trade for a free recharge, so I did the deal. If it works for another year, great.. if it gets damaged somehow, I'll figure it out from there.

Re: r-12 to 134

Reply #4 – June 01, 2005, 07:04:28 PM

If your system if marginal with R12, it will be even worse with R134a. The fact that your system is cooling poorly with R12 indicates something is wrong...low charge, line obstruction, bad fan clutch, air in system, worn compressor, dirty condenser/evaporator, etc.

The $30 R134a kits are called "Death Kits". You never open the system, but add compressor oil, stop-leak(sometimes), and refrigerant. This method can work, but it can also grenade your compressor.

The only way to get the performance of R12 without the cost is a substitute (unless you're willing to buy a high-performance elec. fan and install a new condenser). Substitutes have their own drawbacks. Most are blends, and blends leak out at different rates. If you start with a blend of 80%-A and 20%-B, you may end up with 90%-A and 10%-B after a time. This isn't a good think when "A" isn't miscible with the oil and "B" carries all the oil throughout the system. Another is that most AC shops don't deal with substitutes and don't know anything about them. Each substitute requires different fittings and sets of tools to keep from cross-contaminating systems.

Re: r-12 to 134

Reply #5 – June 02, 2005, 01:01:41 AM

I just did a conversion on my 84 turbo coupe. Really I took a good compressor and Lines and evap from my 85 corgar 2.3 parts car. Then I drained the compressor over night so the ports were pointing srtight down. Also before I installed anything I flushed every last piece with Interdynamics A/c System Flush. It made everything inside look brand new. I also went and bought the full system o-ring kit.Also me and my buddy flushed it with nitrogen also we had it vaced down it 30psi for about 2hours. I've had it in there with the R134a for about 3weeks it works good. Its not as cold as the r-12 but its pretty close. I also jst added tonight a can of the Maxi cool additive it supposed to help it get colder and colder faster. Any take your time and it should work out. Also I do have dual electric hayden fans one there adjustable controller. And yes its the factory R12 evap. Also if you have to much oil in any A/c system it won't cool very well, maybe when you got it filled in mexico they added to much oil. Also there is and alternative its called FREEZE 12 It can be put right in with r-12. do a google seach on freeze 12 its about $15 a can but you need there fittings and can tap just like r-134 but is supposed to be colder and its legal and less work

Re: r-12 to 134

Reply #6 – June 02, 2005, 11:39:23 AM

Quote from: ipsd

Also before I installed anything I flushed every last piece with Interdynamics A/c System Flush. It made everything inside look brand new.

You shouldn't flush the liquid line, becuase it contains the orifice tube. Also, any lines with a ler or filter in it should be left alone or replaced.

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Also there is and alternative its called FREEZE 12 It can be put right in with r-12.

It is illegal to add Freeze 12 to a system that already has R12 in it. You must recover the R12, then add the substitute. Freeze 12 is 80% R134a.

This page has a lot of "how to" A/C procedures.

Re: r-12 to 134

Reply #7 – June 02, 2005, 11:28:52 PM

I have also read about a smart orifice tube that can beinstalled that helps boost the performance of the R-134a. Has anyone tried this. Also my O-tube is in a cripped line and I was wondering if I cut off the collar and chaged the O-tube if I could just crimp it back together with a hydralic hose collar like I sell at work for Gates brand hyd. hoses. Sorry about the leagel issue from what I read it was but I guess they could of had a type-o . Also when I flushed everything on my system everything was off the car except the part in the dash and yes I replaced the filter dryer. I did flush the line with the O-tube also. why is that bad?

Re: r-12 to 134

Reply #8 – June 03, 2005, 12:21:17 PM

Quote from: ipsd

I have also read about a smart orifice tube that can beinstalled that helps boost the performance of the R-134a. Has anyone tried this.

The Smart VOV (variable orifice valve) senses system pressure and shifts to a smaller metering area when a certain pressure is reached. This normally occurs at idle and helps reduce vent temperatures.
From reading the A/C boards [autoacforum/aircondition], it looks like they work as advertised for the most part.

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Also my O-tube is in a cripped line and I was wondering if I cut off the collar and chaged the O-tube if I could just crimp it back together with a hydralic hose collar like I sell at work for Gates brand hyd. hoses.

All the part stores sell an orifice tube repair kit.

They retail for about $20. You'd need one of these to install the Smart VOV unless you order a liquid line with it already installed. It looks like Ready Aire does that.

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Sorry about the leagel issue from what I read it was but I guess they could of had a type-o .

Although illegal, the EPA has never charged a private citizen with this offense. Several years ago, some moron added R134a to my R12 system and it ran fine for over a year until a small leak lead me to take it to a real A/C shop. That's when I found out the previous goober had mixed refrigerants.

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Also when I flushed everything on my system everything was off the car except the part in the dash and yes I replaced the filter dryer. I did flush the line with the O-tube also. why is that bad?

Flushing the part in the dash (the evaporator) is good. Basically, flush the evaporator, condenser, and discharge line (if it doesn't have a ler) with something like kerosene or brake cleaner. Flush the compressor with clean oil. The procedure for this is on the FAQ page I posted. The reason you don't want to flush the orifice tube is because there is a change some nasty bits will clog up the orifice.

Re: r-12 to 134

Reply #9 – June 03, 2005, 01:31:10 PM

Over a year, huh? Great.. so this could very well outlast the engine itself. :D

(if my 3.8 dies, I'll be finding a way to put the 351 in there.. and I'll try to deal with the A/C properly at that time)