a/c temps

[4AU4LIFE]

I just recently got my car back and the a/c system was converted from R12 to R-143A. I drove the car home on interstate and had the a/c running most of the way. I don't like it to cold so I would periodically turn it off and then back on. I was blowing a pretty steady 35-38 degrees out the vent. I have a thermometer in the vents so I could monitor it.
I got to my first stop and turned the car off for a few minutes. Upon restarting the car, a mist/puff of vapor came out of the center vents and then I had no a/c. The air coming out was 75 degrees! I then turned it to heat but got the same temp of air coming out. I was pretty bummed that I had just got the car back after so long and now my air doesn't work.
Well, I drove it the next night and turned it(a/c) on again only to have it work properly? I did notice that it takes a couple of minutes to cool off the interior though. I don't drive it during the day, rather mainly at night and everything seems to be working.
My question is since I converted systems, should it take a little longer for the air to get cold? Or could there be another underlying problem that I'm not aware of?

 

[Ojas]

Based on my experience, there's little difference in temperature between R12 and R143A.

Have you noticed any relation between coldness and vehicle speed? If so, you might want to check the fuses for the condensor fans. I think the fuses in the box under the hood.

When the one or both fuses are blown, you'll notice the A/C seems to work fine at speed (since air is blowing thru the condensor), but the A/C seems weak when parked or at low speed.

 

[4AU4LIFE]

Well it happened again this weekend. I drove up to Atl. on friday and everything was working great. I get up Sat. and the stupid thing wouldn't blow cold for anything. Luckily CHudson was there and let me use his service manual. I ran a/c self check and it appears that the mode door is sticking. I also notice the right side condensor fan isn't running, blown fuse so it was no big deal.
After the show sat. night I get in to drive to Sangria's and the a/c is blowing cold again?!?!?!?!ARGH !!
But now I have noticed that it won't change temps. It only blows air at 38 degrees. I am so confused. I guess this means I need a new control head.
ChaChing $$$$$$$