Air con issues

[Ryannn]

Hi all, I'm after some help with my daily again please. The jag people aren't very helpful and I know there's loads of knowledge here!

The air con in my S-Type has stopped working. It just blows a blast of warm to hot air instead of cold. Is it worth getting it re-gassed or is it likely to be much more sinister? Thanks!!

[ChasR]

If you do get it regassed take it to somewhere who will perform a vacuum test or it could be money down the drain.

I did this with the Clio. Sure it was £70 but it probably would have cost me that with the Halfords cans on trade and my system had a clean bill of health .

However, get them to check the level first. On two cars I have owned the compressor was shot on both cars (seized).

[DarrenW]

I had the aircon on my E36 regassed just yesterday. £50 at Kwik Fit. Takes about 45 minutes or so. They plug it in to a machine and it drains any old oil and gas out, then tests the system for leaks (takes about 10 minutes apparently), then it automatically refills the system with the correct amount of oil and gas. If it fails the leak test you don't pay.

Worth every penny, my car is freezing cold inside again

[Ryannn]

Nice one, that's just the sort of info I was after! Thanks!

[colnerov]

Hi, the most common places the leaks are from are the condenser, right up the front in front of the main water rad, and the seal at the front of the compressor. so check these areas first for an oily and dusty patch. Then as said they should do the vacuum test for leaks before regassing. If your lucky someone has had a fluorescent dye put in and this will show up leakage areas under a UV light.

Colin

[BigDaftAl]

A vacuum hold isn't really the best method for leak testing, its main function is to boil off any moisture in the system (lower atmospheric pressure = lower boiling point) A system that leaks under normal operating conditions, i.e. under pressure, may well not leak at all under a vacuum as the forces acting upon seals the opposite way can actually mask a duff seal.

If you suspect it is actually leaking then it's best to get it filled with nitrogen and leak tested using a handheld detector. It's a big no-no to regas a system that is known to be leaking ;-)

Usual culprit in my experience is a pierced condenser (rad) usually through impact or corrosion or corroded/chafed wiring to the compressor. Chances are though, it's just lost refrigerant over time, this is normal. I can't remember the actual figure off the top of my head but a certain amount of refrigerant loss per year is considered acceptable.

[Ryannn]

Supposedly 10% according to google!

I think it probabaly has just leaked rather than got damaged, it had a funny smell to it earlier in May and now it's just not getting cold. I'll go out tomorrow and try and get it done.

[georgeb]

Jun 11, 2015 19:21:02 GMT BigDaftAl said:

A vacuum hold isn't really the best method for leak testing, its main function is to boil off any moisture in the system (lower atmospheric pressure = lower boiling point) A system that leaks under normal operating conditions, i.e. under pressure, may well not leak at all under a vacuum as the forces acting upon seals the opposite way can actually mask a duff seal.

Exactly. When I replaced my condenser and dryer the A/c place used vacuum and pronounced it leak free before a re-gas. No it wasn't, I'd left a loose joint on the condenser and a day later had no gas again.

If you can get a pressure test, that'd be the way to go. Unfortunately, that level of technology hasn't reached here yet but fortunately a re-gas is only a tenner.