OK, this is my first time using this system, but I am desperate for answers, so please bare with me...

I have a 2005 Ram 2500 with the 5.9l and my a/c loses charge in one day. I have taken it to the shop, no joke, about 11 times. So far, no visible leak has been detected but I have replaced High side hose, low side hose, fan clutch, Schrader valves and gaskets at the rear of the compressor. All in all this shop has charged me $1100 and no fix yet.
I am have no idea what to change next, and I am not going to keep throwing money at the repair shop. Any ideas??? I am very surprised that a leak so rapid can go undetected. Thanks for listening - Andy

 

Welcome to the site, your evaporator core is probably leaking, that's the core inside the heater plenum. The system should not have been recharged if it couldn't hold a vacuum, I would go back to the shop and complain, get them to pull a vacuum and see if it can hold it.

 

Thanks for the reply!
The shop told me that it was holding a vacuum. They also ran a camera behind the dash while I was present, and saw no signs of leakage. A friend of mine told me the problem might be related to the accumulator...any thoughts?

 

You won't find a leaky evaporator with a camera the leaking is usually inside the heater plenum from the bottom of the evaporator itself, they rot away. A good freon detector will find it by checking the drain from the evaporator or even at on of the vents with the fan on low. If it is losing the charge in one day the leak is small but a freon detector should find it wherever it is. If it holds a vacuum with the gauges on perhaps it's one of the service ports leaking after the gauges are removed, About a month ago I had this on a ford F150 I just used a fairly thick o ring in the dust cap and tightened it down, no leaks.

 

The o-ring in the dust cap is a great idea. I will try that and see if anything improves. If not, I will "bite the bullet" and take it to someone with a freon detector. If I am correct, the evaporator is a fairly large task involving dash removal, right? Really appreciate you taking time out of your day to respond. Thx-Andy

 

Freon detectors work some of the time, the other times they lie like crazy. Seen it to many times. Why didn't you put a new Schrader valve in it?

I would have some die put in the system and check it with a black light. Easy and quick. IF it is leaking down that quick it should be no problem to find. I have seen them pass the vacuum test and leak like a crazy under pressure.

 

If you buy an expensive freon detector most importantly keep it clean and respect it as a measuring instrument, it will always work properly, I didn't drop the charge and replace the schrader because the owner didn't have time and the truck was about to leave for up North. If the evaporator core is leaking you will have to put one heck of a lot of dye into the system to find ANY trace of it, I'm not a believer in adding dye. If the leak is external you will likely see the tell tale trace of refrigeration oil and you don't need to waste freon to confirm it.

 

$1100 and still no fix?? I would be asking for some money back. That is crazy. Have they even asked you about dye or using a freon detector? If not you are at the wrong shop!! Take it to someone that specializes in A/C. You are just throwing away good money.