Sniffers give lots of false alarms.
AC Recharge Kits
- Thread starter BMW Dom
- Start date
I think we've already touched on all of these topic here - thanks.
Dye's can be hard to find too and take time. Most of the time, there will be an oily residue where the leak resides.
I paid £150 to recharge the AC on my Wifes Dacia Logan as it wasn't working when we bought it. It held a vacuum without issue so they filled it up and it worked perfectly.
6 weeks later the AC stopped working again. The condensor and radiator were both in poor condition with substantial rot to the fins. I replaced both and filled the A/C up from empty using one of these cans costing £30. I just slowly added it until the air was blowing sufficiently cold. That was about 6-7 weeks ago now and the A/C is still perfect.
My Fathers Alfa Giulia's air coniditioning stopped working a short while ago. The low pressure side is showing 10psi with the compressor running so planning on topping that up this weekend using the same method.
A bit of common sense and they seem to work well. The cans I used apparently contain the appropriate oils too.
6 weeks later the AC stopped working again. The condensor and radiator were both in poor condition with substantial rot to the fins. I replaced both and filled the A/C up from empty using one of these cans costing £30. I just slowly added it until the air was blowing sufficiently cold. That was about 6-7 weeks ago now and the A/C is still perfect.
My Fathers Alfa Giulia's air coniditioning stopped working a short while ago. The low pressure side is showing 10psi with the compressor running so planning on topping that up this weekend using the same method.
A bit of common sense and they seem to work well. The cans I used apparently contain the appropriate oils too.
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I wouldn’t touch that stuff unless you need cold air right now and are OK with the consequences or if that car last stop is the junkyard.
AC techs hate that stuff - it can clog recovery machines. AC Pro does use a polymeric sealer with a little MeCl(methylene chloride) as a seal swell agent. Methylene chloride is corrosive to aluminum under certain conditions.
It’s not just an automotive AC thing, similar things to AC Pro are being hawked to HVAC/R techs. I’ve seen a HVAC tech try to use this stuff to fix a leak in a indoor unit only to fail a few weeks later. They ended up having to replace the coil.
fix it right. The parts on a BMW aren’t cheap and it would suck to do the work twice in any case.
AC techs hate that stuff - it can clog recovery machines. AC Pro does use a polymeric sealer with a little MeCl(methylene chloride) as a seal swell agent. Methylene chloride is corrosive to aluminum under certain conditions.
It’s not just an automotive AC thing, similar things to AC Pro are being hawked to HVAC/R techs. I’ve seen a HVAC tech try to use this stuff to fix a leak in a indoor unit only to fail a few weeks later. They ended up having to replace the coil.
fix it right. The parts on a BMW aren’t cheap and it would suck to do the work twice in any case.
I saw multiple comments from people saying how the oil or sealers in these AC-in-a-can things "clog" up the equipment that mechanics use. They have to have a way to deal with that, don't they ? Not condoning people's use of these cans but plenty of them have to end up in shops eventually. Can they clean the filters (I think someone mentioned filters) or more likely, have to replace them frequently ?
garageman402
$100 Site Donor 2024
My compressor stopped working I assumed due to low pressure. I pushed the Schrader valve in, still had a tiny bit of pressure, so I assumed the system hadn't sucked in any air/moisture. I bought the can pictured in the OP's first post, noting it had oil and seal swell, didn't notice the sealer. The system was last charged 10 years ago, so it's a good assumption just normal loss from seepage had occurred.
So I used the whole 20oz can, and low pressure side was barely out of the "low" white area (around 25#). The gauge is reusable, so I returned the empty can for my $10 deposit (CA requires a $10 deposit to ensure proper return/recycling of the can), and bought two of the 12oz cans. I put in one 12oz can and the low side is now not quite to the middle of the green area around 35#. Revving the engine dropped the pressure to 25 so I did that to get the most out of the can, then at idle got the 35# reading. You can tell when the system is not taking any more, as the can stops feeling cold.
This is the 2000 Pontiac Montana minivan with rear A/C, which takes 2.88lbs (46oz). So far I have put in 32oz, and have the reading around 35# on the low side at idle.
Two questions: (1) The normal seepage of refrigerant over 10 years would not deplete much oil, so the oil contained in the first 20oz can should be enough so adding the 12oz can(s) with no oil would be ok? (2) Knowing there was very little refrigerant left in the system, would it be wise to add the second 12oz can to bring total added refrigerant to 44oz?
Thoughts?
So I used the whole 20oz can, and low pressure side was barely out of the "low" white area (around 25#). The gauge is reusable, so I returned the empty can for my $10 deposit (CA requires a $10 deposit to ensure proper return/recycling of the can), and bought two of the 12oz cans. I put in one 12oz can and the low side is now not quite to the middle of the green area around 35#. Revving the engine dropped the pressure to 25 so I did that to get the most out of the can, then at idle got the 35# reading. You can tell when the system is not taking any more, as the can stops feeling cold.
This is the 2000 Pontiac Montana minivan with rear A/C, which takes 2.88lbs (46oz). So far I have put in 32oz, and have the reading around 35# on the low side at idle.
Two questions: (1) The normal seepage of refrigerant over 10 years would not deplete much oil, so the oil contained in the first 20oz can should be enough so adding the 12oz can(s) with no oil would be ok? (2) Knowing there was very little refrigerant left in the system, would it be wise to add the second 12oz can to bring total added refrigerant to 44oz?
Thoughts?
Shops can install a pre-filter but its the valves in the R&R machines that get contaminated and plugged. There’s also a filter and drier element in the R&R machines. But many of those AIO refrigerants use a polymeric stop leak and MeCl as the seal swell agent. The stop leak portion has an affinity for water.
This is really interesting. I bet someone more experienced can say but I think the proper way to do this would have been to have the entire system evacuated and the oil drained and then add the correct amount of oil and refrigerant.
My thoughts are that if it's cold, don't bother adding anymore until it fails to get cold. I wouldn't add anymore because there's no real way to tell exactly how much you have in there, I think the pressure is not an accurate way to tell how much is in there. Too much will also cause your compressor to burn out.
If you own a BMW, shouldn't you also have the means to pay a shop to look at it for you? I don't get why people buy "higher priced" European vehicles but don't want to shell out the money for proper maintenance.
If you read the whole thread, that's exactly what the OP did and sounds like he will do.
