jedwards99

Hello:
I need to remove the a/c under the dash and was wondering if there is anything special I need to do?? I have heard that the system needs to be purged first?

BigIron22

The freon is supposed to be recovered. (pulled from the system into a storage tank via a recovery unit.) So it is not released into the atmosphere . but you can just bleed the pressure off the system through the service ports before opening it, not the correct way but you can do it. but it is not good for the environment!!!!!!!! after the system is put back together the system needs to be vacuumed ,to remove air and moisture, then charged with freon.

2+2GT

Before you do that, why do you "need" to remove it?

MBDiagMan

It is not only "good for the environment" to recover the existing refrigerant, but releasing the refrigerant into the atmosphere VIOLATES FEDERAL LAW!

Whether you choose to release the refrigerant or have it recovered, seal up everything so that the moisture in the air does not contaminate the system while it is apart. Then after reassembly, the system will need to be evacuated and recharged.

jedwards99

Thanks guys for the heads up. There are a few reasons I want to pull the A/C. There is some corrosion around the fittings that I would like to clean, Im installing new carpet and to blow out and clean the unit....original unit and has been sitting for quite a while.

2+2GT

Not sure what corrosion you refer to, but cleaning the coils, and replacing the carpet are things I have done many times with the unit installed. There is a support spike on the underside, with a locknut. It is possible to loosen the locknut and retract the spike with the unit installed, and you have to do that when pulling the carpet.

Oh, and that whole "CFC gonna kill the planet" thing is almost as dead as "global warming".

If you have R12 in your system, be prepared to lay out a couple hundred to put it back. Alternatively, you could use "Freeze 12" which seems to work, but I know nothing about it's long-term effects on the system.

You could convert the system to R134, but that would cost more than R12.

MBDiagMan

It will NOT cost a couple of hundred to recharge with R12! The price of it has come down dramatically. I bought some last year for $15 a pound and it takes less than 3 pounds to charge one of these units.

In addition to that, a reputable a/c shop will recover the refrigerant and recycle it so that it can be put back into the unit. In that case it will only cost for the labor to do so assuming that the system is in good shape and properly charged.

The misinformation surrounding R12 is astonishing!

All that said, I have effectively over 50 years of experience with automotive a/c starting in my Dad's shop when I was a kid. I can tell you from experience that disturbing an operational a/c system is a BAD idea. There are a zillion problems that it can cause. Unless you REALLY need to remove the unit, DON'T DO IT!

2+2GT

Nice to know about the cost of R12. One of the advantages it had was low cost, way back when. Another was it was no-corrosive.

I recall reading about 10 years ago, when the cost was sky high, R12 was the #3 substance being smuggled across the Mexican border, right up there with cocaine and heroin. Ya see, it was cheap to make, and legal in Mexico.

And yes, if you have a sealed system, don't mess with it. My system was charged in 1990, and a few years later, when I pulled the heads to port match them, I wired the still-connected compressor to the fender apron. It still blows ice-cold today, too.