Can air conditioning be recovered after leaking?

Mysterae_

Mysterae_

Mysterae_

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A few months back I tried to get the aircon of my 2012 640D regassed but the bloke doing it did a leak test with a sniffer first and it was deemed pointless as it was leaking everywhere; under the dashboard and various places in the engine bay.

Apparently if it's left too long the seals dry out and can't be recovered. I was told it was uneconomical to fix as all the seals would need to be replaced - dashboard out etc. So I left it.

I have been wondering though, how true is this? Is there a chemical that can be added to seal the leaks and has anybody had any success with it?
 
If you really want it back up and running I’m sure you could probably DIY some, it not all, of it by following guides online. Have you looked for guides in the owners clubs, online groups?

I pretty much always keep my A/C system on as I think lack of use contributes to failure. The only issue with the A/C I’ve had with all my cars is one where the condenser failed, but it had covered 135,000 miles and 13 years on the road. I’ve never used the sealing products personally, so can’t help with that.
 
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As far as I know, the seals that dry out because of intermittent use are the ones on the compressor shaft.
The rest of the joints would be brazed / flared and would not have perishable seals.
There are products that you can add, snake oil being one ;)
 
Mysterae_ said:
A few months back I tried to get the aircon of my 2012 640D regassed but the bloke doing it did a leak test with a sniffer first and it was deemed pointless as it was leaking everywhere; under the dashboard and various places in the engine bay.
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Unless it was an actual air con specialist you took it to, most places that just do a regas haven't got a clue.
 
He was a mobile aircon bloke with a van and had the kit and seemed to be knowledgeable. He didn't charge me for the diagnosis and I did see him with the sniffer wand detecting the leakage, plus he showed me where the UV dye was visible at certain places in the engine. He convinced me, so I just decided to let it be.

It's annoying not having aircon though but I don't want to spend a lot on getting it fixed, being such an old car. Maybe I'll try some snake oil :D or more likely a specialist garage that only does AC for a second opinion like has been suggested.
 
Mysterae_ said:
He was a mobile aircon bloke with a van and had the kit and seemed to be knowledgeable. He didn't charge me for the diagnosis and I did see him with the sniffer wand detecting the leakage, plus he showed me where the UV dye was visible at certain places in the engine. He convinced me, so I just decided to let it be.

It's annoying not having aircon though but I don't want to spend a lot on getting it fixed, being such an old car. Maybe I'll try some snake oil :D or more likely a specialist garage that only does AC for a second opinion like has been suggested.
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Funny you mention it being such an old car, I was just reading your post and thinking that it was too new a car to be leaking from so many different areas. It's entirely possible that one or two components have failed but it would be unusual to need to replace so many components on a 2012 car.
 
geekman said:
Funny you mention it being such an old car, I was just reading your post and thinking that it was too new a car to be leaking from so many different areas. It's entirely possible that one or two components have failed but it would be unusual to need to replace so many components on a 2012 car.
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That's what I started to think, and previously I ran the aircon almost 99%. It system started to get weaker after I had ****-Fit do the aircon while I was in for some tyres. I guess that was my punishment.
 
as an indication of seal state, had they told you how much gas was left in when they pumped it out.
(do any car system have a pressure monitor, since I doubt I'd notice if it degraded and was engaging clutch for longer periods)
 
jpaul said:
as an indication of seal state, had they told you how much gas was left in when they pumped it out.
(do any car system have a pressure monitor, since I doubt I'd notice if it degraded and was engaging clutch for longer periods)
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He said it was zero pressure so probably empty. I've had the AC switched off for a while as it stinks when it's on.

There was an error code when I last scanned it with Carly but can't remember what it was (Carly is crap btw!).
 
I'd suggest it's probably likely to just be damage to the condenser either a stone or just rotten
Any minor leaks found elsewhere could just be because the system is "dry" - the seals haven't been lubricated for some time, so you will get some blow by.

Having done a bit of reading up on it earlier, although commonly thought that it is a completely sealed system, even BMW themselves specify an acceptable amount of refrigerant loss per year (30g) which suggests it's not entirely sealed.

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My old cooper D has a slow leak and lasts about 3 months so I just get a cheap bottle of coolant for around 20 quid and gas it myself for the summer, you can get the leak sealant stuff as well so I might try that next time to see it makes a difference.
 
Thanks for that @Armageus.

I'm wondering if I should take it to BMW as they have the proper diagnostics and will know if it needs oil or not. An independent AC specialist may not. At least I'll know the bottom line what it'll cost and if it's worthwhile.

Thanks folks.
 
An AC specialist will most likely be better than any main dealer frankly. It is after all what they specialise in solely.
I don't buy the whole "it's usually the condenser" thing. Yes it can be, but it often is a leak somewhere on a perished bit of pipe where it's rubbed, or been damaged or just worn out. Or a seal has gone.

You can buy a cheap UV torch online and go out at dark and see if you can spot where it's been leaking (if the UV dye was previously added at some point during a leak test or a regas) but I warn you...it can be a rabbit hole.

Any decent AC specialist will find whatever the issue is quickly, and quote you for repairs so you know where you are at. The whole dash out thing is only in rare cases where the evaporator has gone I think. These are last resort jobs because the labour for that would write a lot of older cars off.
 
Mysterae_ said:
A few months back I tried to get the aircon of my 2012 640D regassed but the bloke doing it did a leak test with a sniffer first and it was deemed pointless as it was leaking everywhere; under the dashboard and various places in the engine bay.

Apparently if it's left too long the seals dry out and can't be recovered. I was told it was uneconomical to fix as all the seals would need to be replaced - dashboard out etc. So I left it.

I have been wondering though, how true is this? Is there a chemical that can be added to seal the leaks and has anybody had any success with it?
Click to expand...

This is a tradeperson's way of saying "it's broke, but I don't want to fix it so please don't ask me to, I just re-gas them"

Definitely get a second opinion from somebody willing to do the work to fix it. People above have mentioned a whole bunch of things it could, ring round a few of your local garages and talk through the problem and see what their responses are. Anybody who umms and ahhs and sucks through their teeth about how expensive it will be are telling you they don't want the job. Move on and find somebody who's attitude is "sure, bring it down, we'll see what we can do"
 
Find somewhere (most places should do it) who will use nitrogen, it's illegal to fill with ac gas then look for a leak if it's suspected the system is leaking, hence usung nitrogen.
Any decent garage should be able to trace any leaks in short time.
We won't touch any ac system thats had leak solution in it as it completely trashed one of our ac machines when we recovered the gas from a car that had it in it.
 
Ideally they would have given you specifics I.e which joints are leaking, is the compressor shaft leaking, has the compressor failed and spilt its guts throughout the system, is the condenser damaged etc. I think you need to get it looked at again.

For example replacing say an o-ring on a compressor pipe connection on an empty system costs pennies and takes minutes.
 
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