Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: Panic mechanic! on June 16, 2010, 05:18:02 PM

Title: who deals with a/c?
Post by: Panic mechanic! on June 16, 2010, 05:18:02 PM
OK looking for a birty who works with  vehicle air conditioning! So I can save some earache!
Title: Re: who deals with a/c?
Post by: Nosebolt on June 16, 2010, 05:20:31 PM
you talking about a gassing service or do you have a fault, if gas i know a man in Bristol who does m8s rates, but you would have to go to him
Title: Re: who deals with a/c?
Post by: Panic mechanic! on June 16, 2010, 05:31:05 PM
Tina's new bug has air con   but there is something wrong with the system as its not chilling at all, I had it gassed up and it worked but overnight it stopped so I am thinking there is a leak somewhere in the system, I was just wondering if there is a DIY way of checking for leaks in the system. weird thing is their does seem to be a fair bit of air pressure in the system. so need some more techy  help on diagnosing, (the compressor is switching fine, not sure what to look for next)
Title: Re: who deals with a/c?
Post by: Nosebolt on June 16, 2010, 05:33:25 PM
sorry m8 beyond me, but best of luck
Title: Re: who deals with a/c?
Post by: Mike Pavelin on June 16, 2010, 06:48:34 PM
There are many things that can stop it cooling efficiently including

Not enough refrigerant
Too much refrigerant
Incorrect refrigerant
Faulty expansion valve
Moisture in system
Poor air flow through condenser
Faulty evaporator temp probe
Faulty cooling fan
Faulty compressor
Faulty door in Hevac unit
Faulty climate control electrics

Obviously, the most common is refrigerant loss, small leaks can be difficult to detect even for professionals as some components are inaccessible. If you think you have a leak and the compressor still runs, mix up some fairy liquid and water and put it in one of those trigger pump type bottles you get cleaning products in and spray all the visible components, including the service ports with the caps removed. Run the A/C up and watch for bubbles. Anything else is really a professional job.
Title: Re: who deals with a/c?
Post by: Panic mechanic! on June 16, 2010, 06:56:36 PM
I am leaning more towards a loss of refrigerant as when it was  filled up to the correct level  it worked but within a matter of less than 12 hours it had stopped cooling.
assuming  it may be that (and if  I find a leak) Is it ok to take apart the system and replace the 'o' rings  if they have become perished? or will it still need the system vacuuming out?
Title: Re: who deals with a/c?
Post by: Tragic on June 16, 2010, 07:00:11 PM
It will require degassing proffesionally. R134a is nasty stuff
Title: Re: who deals with a/c?
Post by: Bubba on June 16, 2010, 07:15:30 PM
fill it with petrol under presure then check for leaks with a blow lamp i think you will know when the leak has been located
Title: Re: who deals with a/c?
Post by: Mike Pavelin on June 16, 2010, 08:05:17 PM
fill it with petrol under presure then check for leaks with a blow lamp i think you will know when the leak has been located

You jest, but it has been known for cowboy operations to fill systems with Butane or Propane, which is much cheaper and actually make quite effective refrigerants, but have certain undesirable properties that make them somewhat unsuitable.
Title: Re: who deals with a/c?
Post by: Bubba on June 16, 2010, 08:06:35 PM
wow there realy are some scary operators out there
Title: Re: who deals with a/c?
Post by: Dave The Sparky on June 16, 2010, 08:20:41 PM
Our old Audi had a green dye in its refrigerant as i found out when i bust one of the pipes by accident :icon_redface: a bit more ozone layer gone now. Assuming that the same stuff would of been used in a new VW then it would suggest that the problem has been there before as i dont think you would miss even a hairline leak with that stuff as the dye was a lovely shade of luminous green.
Title: Re: who deals with a/c?
Post by: Mike Pavelin on June 16, 2010, 08:30:40 PM
It could have the UV dye in it if it's just been regassed. Helps leak detection in visible areas at least. BTW, it is very illegal to deliberately release refrigerant into the atmosphere or even charge a system known to be or even suspected of having a leak. Carries a huge fine if you get caught.
Title: Re: who deals with a/c?
Post by: Dave69 on June 17, 2010, 08:20:02 PM
shine a uv light over the engine (not in direct sunlight) any leak should be visible as there is a marker dye injected into the system for that purpose.