[Ralph]

I guess I need new freon in the AC system. Or a recharge, I know that since 1995 the ozone friendly 134-a had to be put in new cars. Obviously my '91 has CFC-12. What will be involved? Can they just change the freon, or do they have to change the compressor, etc? My Chilton repair book recomends that all cars with AC be maintained, and to do that it is good to run the AC for 5 or 10 minutes each month to keep the seals from leaking no matter what the season. My dad never did this and it blows warm. I did follow this guideline for my previous old car for years and it still blew cold. Later this week I will get a price quote from Midas, etc. Does anyone have experience with this??

 

[Mad'lac]

I know that they change the o-rings and seals and the oil. Not sure what else is involved but it can be costly.

 

[Katshot]

All you need to do is take out the "winter" freon, and put in the "summer" freon

Actually Ralph, the "DEFROST" mode turns on the compressor for you and thereby keeps the refrigerant system properly maintained, so you needn't worry about turning on the A/C over the winter.

As for switching to R134a, generally it's just a matter of flushing the system, changing the drier, installing the new service ports, and finally installing the new oil and refrig.

 

[Elvis]

Canucks don't need AC. Roll down the windows!

 

[Ralph]

Canucks don't need AC. Roll down the windows!

Hey, we were already 80 F yesterday Elvis! My winter igloo melted last month!LOL

 

[Ralph]

Thanks for the defrost info Kat, but that must be the problem, my dad never winter drove it to use the defrost!

 

[AKPsiMC03]

and R-12 system which is converted to R-134a will not cool as well as a straight R-12 or R-134a system. The R-134a needs a bigger compressor and more pressure to cool. the old R-12 will not cool that well, so at best, a converted system will give you OK airconditionig and nothing more.

 

[Katshot]

Actually, it doesn't need a bigger compressor. It needs a bigger evaporator and condensor because the R-134a doesn't suck up as much heat as the R-12 and it transfers more slowly.

 

[BeelzeBob]

I thought switching was going to be a big deal but it wasn't. The new system cooled fine. I didn't even notice a difference...

 

[Katshot]

Vent temps tend to be "slightly" higher after the retro-fit but usually the system is able to still cool sufficiently.

 

[Ralph]

Vent temps tend to be "slightly" higher after the retro-fit but usually the system is able to still cool sufficiently.

Midas wants 325.00 while the Caddy dealership wants 400.00. Why would the vent fan blow warmer, it is just outside air? And why isn't the new freon as cold as the old stuff? Does this mean that all new cars don't have really cold AC????

 

[kcnewell]

Midas wants 325.00 while the Caddy dealership wants 400.00. Why would the vent fan blow warmer, it is just outside air? And why isn't the new freon as cold as the old stuff? Does this mean that all new cars don't have really cold AC????

Ralph, Don't get yer panties in a bunch here! I had my car converted to R-134 two years ago, It'll freeze your ass of when it's 100 degrees out.....Works great!

 

[Ralph]

Ralph, Don't get yer panties in a bunch here! I had my car converted to R-134 two years ago, It'll freeze your ass of when it's 100 degrees out.....Works great!

Thanks, that's all I wanted to know!! PS, how did you know I wear panties.....LOL

 

[kcnewell]

It's written all over your face! LOL!

 

[Katshot]

Ralph,
By "vent temps", I meant A/C output temps (measured at the vents). The Retrofit cars tend to be slightly less efficient and they end up with slightly higher vent temps.

Newer cars (cars that came from factory with R-134a), Have been designed to work with the newer refrigerant and therefore have larger components where necessary to provide the same low vent temps that the older R-12 cars did. It's just when you use the R-134a in the older (smaller) R-12 systems that you will get the slightly lower performance.

 

[Mad'lac]

You live in Canada!!!! What the hell do you need A/C for?!?!?!?!?
Be happy that the heater works.

 

[Ralph]

You live in Canada!!!! What the hell do you need A/C for?!?!?!?!?
Be happy that the heater works.

I'm not sayin' anything bad to that dude, I just saw "Texas chainsaw Massacre!!"

 

[Ralph]

OK, today I noticed that the service AC or whatever light stays on longer after startup and longer than all the other lights. I guess it knows it is time for a change.

 

[Ralph]

Actually, it doesn't need a bigger compressor. It needs a bigger evaporator and condensor because the R-134a doesn't suck up as much heat as the R-12 and it transfers more slowly.

Turns out you are right on the mark. Midas said I could go with a bigger condenser if I wanted it to be colder, but I won't bother. They said as long as the RPM's are up, like on the highway, it will be cold. I don't use it in the city. Oh, yeah, seals, oil and freon as well, of course.

 

[Ralph]

OK, now I am really confused! today we had a fairly hot day (88 F) and assuming my AC did not work, because it wouldn't last month, my better-half said "turn on the damn AC" Knowing NOT to argue anymore, I did! IT WORKED!! Why did it work now and not before? Could it have something to do with the sensor on the dash, because maybe last month it was not as hot? Why would the car not let me manually use AC, or is it under total control of the computer? I am very confused, but with these cars I am getting used to it. I put it on AUTO, then to 18C, the second lowest setting and presdo, ice cold air!? I thought if you wanted cold AC, you put it to the lowest setting which in celcius is 16C. I do understand the workings of a thermostat, but what gives? Oh well, at least I just saved 325 dollars at Midas NOT getting it fixed!