Boxster A/C recharge

[vrauba]

Has anyone tried to recharge (top off) their A/C refrigerent? You can buy R-134A kits on eBay and I was wondering if there is anything to prevent one from doing it themselves thereby saving tons of cash. Any insights would be appreciated. This is for a 2000 Boxster.

[0586slb]

You did not mention why you are considering buying this kit. Is it because you feel the A/C is not getting cold enough? Have you had it diagnosed as being low on gas? Have you opened the A/C circuit to change a component? Its not really a DIY job. I presume the "kit from eBay" is just a bottle of R-134A and an adapter that you hope will connect on to your service valve?

There could be many reasons that the A/C is not getting cold enough, these can only be effectively diagnosed at the dealer or by professional A/C engineers. If your A/C circuit has been leaking, chances are that the refrigerant oil has been leaking too. If this is the case, the A/C tech has to fix the leak, work out how much oil is in the system, evacuate all the old R134A, flush with liquid nitrogen, evacuate again, then refill with a combined mixture of R134a and PAG oil. Which service valve do you use with the kit? The high pressure or low pressure one?

[vrauba]

Thanks for the input. Yes, I have a minor leak somewhere, but it is minor since it takes about 6 months to loose enough refrigerent to affect the cooling of the car. Porsche dealer in my area recharged the system last spring while the car was still under warranty (I felt A/C was not cold enough) and dealer service department claimed it was a tad low in pressure but there were no leaks. By late fall, I noticed a loss in cooling efficiency again so I brought it back in the last month of my warranty. They evacuated and recharged the system and again claimed there were no leaks. I don't use A/C in Colorado over the winter so it was not until last week that I tried the A/C again. To my dismay, there is no cooling at all now. That confirms there is a leak. Dealer now tells me that to evacuate and repair the leak will cost more than $300.00 and the car is now out of warranty ....so too bad for me. :-( No guarantee on their diagnosis/repair from last year.

Kits are available that come with (3) 12oz. cans of R-134A refrigerent, leak stop with dye, PAG oil lubricant, hose, pressure gauge and couplers that attach to low pressure end of compressor. All that costs around $50.00 and I was hoping that the leak stop may fix the problem since it's probably a dried O-ring, or something minor like that. I'd also check to see if there was a mechanical problem by searching for the red dye. I was going to guess on the amount of oil lubricant...maybe 4 oz., or so. My concern is that I might not really know what I'm doing and I don't want to do serious damage to my system. I figured $40.00 and an hour of my time is a reasonable gamble, but NOT if I screw up my car. If it doesn't work, I can bite the bullet and bring it to a professional repair shopis my reasoning.

Any more thoughts? Am I underestimating what it takes to recharge/repair my system?

I may also contact Porsche customer care, but I'm not holding my breath that they'll do anything with the dealer and mis-diagnosis. Thx.

[0586slb]

I can understand you may not have the resource to go to the Porsche dealer, also they seem to have mis-diagnosed it for you. Have a go with Customer Care, they may surprise you!! But I'd still advise a professional independent. They should have a 'sniffer' probe that loves the smell of refrigerant gas, and can find very small leaks.

I am in no way judging your ability to do this, but here's a few A/C facts to help your gamble:

1. PAG oil. Too little, or introduced in the wrong place, compressor seize. Too much, hydraulic lock in compressor or clogged receiver/drier.

2. The system works by passing liquid R134a through a tiny hole (restrictor) so it vapourises in the evaporator thus causing a cooling effect. Any dirt introduced to the system, will clog the restrictor. Any water vapour introduced, can freeze in the evaporator - and clog the system. To repair a clogged restrictor, its in the evaporator thats buried as far within the dashboard as you can get!

Leak Stop - doesn't that try to block tiny holes...?

On a lighter note, I had an old F*rd a number of years ago that was constantly needing topping up with coolant, I discovered a small radiator leak. In went some 'Rad-Weld' solution into the expansion tank. After a few weeks of driving, the level in the tank never moved, but the engine still boiled dry!! The Radweld had formed a solid goo in the exit pipe from the tank.