starlinesusa

I am considering converting my AC to the new R134a. It works good now but topping it off is pretty pricey.

Have been told that the R134a does not blow as cold.

As opinions or suggestions?

John485garage

Yes, my 73 was converted to R134a a few years back. When the outside temp hits 90 or above, it will not be as cold as the original R12.

Good luck

Oldriceguy

I agree with John485garage. Mine has R134a and it's just not very cold when the temps hit 90 or above.

starlinesusa

I live in Phoenix AZ ,so I guess the conversion would be an issue. Right now, my AC is cold it just doesn't blow really strong. The cabin is so small that it keeps it plenty cool... but I would like it stronger.


Perhaps the answer is some sort of update on the unit??

joewill

do a google search on the pros and cons of r12 vs r134a. you can use r134a but there are tradeoffs such a more leaking potential due to a smaller molecule, unless your replace hoses and lines etc. boiling points are different so the heat exchange is different. to do it right you make the A/C parts vendors pretty $$ happy.

but just top it off with one can a season (plus the proper oil).. you really have no choice since r12 is really hard to find and rare and expensive.

oledave60

Stay with r12 as long as you can. These old systems just don't work well, if at all with 134a. There is plenty of r12 on ebay for $30 to $35 per can and if you really won't to do it right you can get a r12 license for $20 on line.

starlinesusa

Dave, that is great advice. Thank you. Even out here in Phoenix, my A/C is cold and it does keep the cabin cool. I guess I wish ti would just blow stronger.

Ih ave an 1973 L-82 T-top auto

oledave60

I put a blower from a 96 Corvette and it made a lot of difference for the better. The squirrel cage is deeper so you will need to fab a 1" spacer (I used plywood), but other wise it is an easy fit. Also check your voltage at the fan, it may be less than 12. Mine was so I added a relay and now have about 13V.

starlinesusa

Great advice. Thank you so much.

It's only 108 degrees here today, so time to take the Vette out for a spin. Its neat because most everyone with a vintage car has no AC..so they drive around early in the morning with their windows down. I drive mid-day with the windows up.

Blue73Shark

Also check all your electrical connections at the switch, motor, relay and ground for corrosion. This can reduce voltage which would make the blower run slower.
Fran

gungatim

I agree, they were designed and sized for the cooling ability of R12, not R134a so they are less efficient. there are other substitutes like the freeze12/hotshot/R414a, they work better than R134a but still require the liners so your hoses still need to be replaced, and since R134a is more available and cheaper it is the more common upgrade. the pro's of R414a is that it cools better and is compatible with mineral oil, so you don't need the synthetic PAG oil or need to flush the system.

stay away from the R12 substitutes, they are hydrocarbon mixtures of propane, butane, and R22. even if they say R12 substitute. you don't need to add to the flammability of your vette

I'm still running R12 in my '95 and my kids cars as well. you can still get R12 on craigslist or ebay, but if you hit garage sales and estate sales, you can often get it much cheaper. I usually find 2-3 cans a year that way, and can get it for <$5 a can, sometimes less if you buy a whole box of someone's old garage stuff...

starlinesusa

That is a terrific suggestion. Thank you. I would be great if I can get the blower fan to have just a little more pop.

69FASTFUN

I had my evaporator and valves rebuilt by Classic air and they suggested to stay with R12 because the 134A does not do well at cruising speeds.

Wrecked82

I had a quality shop convert my car to R134a a few years ago. Now, I live in Houston, home of 90 - 100* temps. A/C works fine. No leaks for two years now. Cool as ever. I can see no decrease in cooling. Just my experience.

Iceaxe

^^^THIS^^^

your experience mirrors mine pretty much. When I bought my 1970 the AC didn't work so I have no clue how cold it was originally. But I had the AC rebuilt and converted to R134a three years ago and it has no problems cooling the car on a 95 degree day in the Utah desert.