air con has died

[dan_b]

Both my compressors leaked through the main chassis seal. The aircon guy I saw said it's a stupid place to have put it because it gets so much thermal cycling and heat soak, but also very little cooling, and it's exposed to a lot of gunk (technical term!).

The chaf seals can be replaced, but if you break open the casing, you don't know what else is going to be going on in a 10-year old compressor that might go pop afterwards?

[audiman]

3b compressor have different service port. That is a proper R12 low pressure valve. The later cars dont have this.

It doesnt really matter, as the system can be filled with the high pressure port. BTDT on 3 S2's now.

[s2avant95M]

ok, a/c dude has changed his position and now says he is willing to gas the system with R134 from the high pressure port, but says he cannot fill it with UV dye to test for leaks because he must use the low pressure port to do this.

[dan_b]

That's not true. I had mine re-gassed with R134 on the high side and they included the UV dye: he injected it in manually with a syringe after gassing up.

It is also possible to fit a low side R134 valve on to the stock Denso compressor as I had them do this to mine when I changed compressors last autumn.

[audiman]

Yes you can fit a retro-valve to the 3B compressor. But not easily to the later ABY/ADU comp.

And yes you can inject Dye after gassing, but it is a lot easier to do so via the low pressure side.

Just get him to gas it, and then go over the accessible pipework and components with a Halogen gas leak finder. Its all easy stuff to do. Sounds like they are being lazy.

Never done one, so dont want to know. It becuase its slightly different, it scares ppl.

[S2central.net]

I think the lack of a low pressure service port is enough to freak the average aircon man out. If it phases them, then you know they haven't seen it before and its perhaps time to seek another 'specialist' or make absolutely sure (by questioning) that they have the skills and equipment to work without the low pressure port.

Totally agree with Tom that adding an LP service port is a good idea before regassing!


Paul

[CliveH]

compressor valve and regassing were the problems with my aircon

[audiman]

What on your S4??? LOL, that is the easiest to do

[SR71]

Ok dudes.

I've been trying to get my a/c working again and today the ABY was at the a/c specialist and sure enough my car is the same - R12 adaptor on the low pressure side so had to try gassing it through the R134 high pressure port.

However, he could only get 20grams of gas into it. The compressor would not engage to allow further pressurisation.

So whats the diagnosis of the gurus?

The guy didn't want to say my compressor was f**ked before he'd tried gassing it via the low pressure port but of course he couldn't.

Audi are gonna set me back £89 for the privelege of hooking up the low pressure port and having a go themselves.

Any suggestions? I like the idea of finding an R12-R134 screw-bayonet adaptor myself
and taking it back to the local garage for an attempt at re-gassing via the low pressure port.

Anyone know of such an adaptor and a source?

Cheers.

[audiman]

You need to vacuum the system for longer. I have managed to do 3 S2 this way. You cant use the compressor to drag in gas via the high pressure side, unless you heat the bottle up as the gas in the bottle is under less pressure than the high side of the car. (bottle is about 5bar ish, and car runs at about 10-15bar)

[SR71]

Cheers Tom.

I don't know how the machine works but the mechanic said it was on the machine for 3-4 hours trying to get the gas in. Do you evacuate the low pressure side first before hooking up the machine? Is it the same process?

I could presumably fit one of these hoses (http://www.sjdiscounttools.com/cpshc6.html) onto the low pressure side and tuck it away for future use right? It'd be nice just to get an adaptor though rather than the hose as well.

Save me going to Audi every time I need a refill.

[audiman]

Cheers Tom.

I don't know how the machine works but the mechanic said it was on the machine for 3-4 hours trying to get the gas in. Do you evacuate the low pressure side first before hooking up the machine? Is it the same process?

I could presumably fit one of these hoses (http://www.sjdiscounttools.com/cpshc6.html) onto the low pressure side and tuck it away for future use right? It'd be nice just to get an adaptor though rather than the hose as well.

Save me going to Audi every time I need a refill.

You dont have to go to Audi. Whats wrong with all these "specialists" . Its not hard. You can try and force the gas in for as long as you like. But if you dont create a good vacuum in the system you wont do it. If you vacuum the system for about 30 mins, the gas goes in easily.

That hose wont fit, they are for converting the specialists old R12 kit over to R134a.

You just evacuate and vacuum the high pressure side and dump gas in the same port. Easy.

Whats the thread size on that port on the compressor?? I think its R12 high pressure size. In that case just fit a R134a conversion valve and then get the "specialist" to swap the hose connectors on his kit and he should be able to fill it up.

[audiman]

http://www.acsource.com/index.asp?PageAction=VIEWPROD&ProdID=245

something like this

[SR71]

Nothing wrong with specialists at all except that I wasn't sure if he knew what he was doing and was just being lazy - like you mentioned earlier in the thread!

He didn't know of any conversion valves like I suggested so I was wondering how specialist he was!

I'll give him a ring tomorrow with the suggestion.

[s2avant95M]

i'm still in the same boat, i went back to my a/c dude armed with all this info and he was still adament my car had r12 gas in it.