Evacuating R-12 systems

call around to your local HVAC/refrigeration contractors... most of them will have the vaccum pump in their truck and can come to you.

-Bret

Pull the cork in yer' garage at 3:00am. No one needs to know..................our environment is f**ked up enough as it is. Another

Doc

I agree, just one good volcano erupting every 100 years or so destroys more ozone that all the CFC that have ever been manufactured have done. But the tree huggers can't control the agenda of volcanoes, and nature doing something isn't as newsworthy as man doing something is. Besides it is only the rich countries that have the restrictions on R-12 and certain other CFC's etc anyway.

To Bret thanks for the info... i'll probably go that route.

To Doc and J....

Theoretically speaking, if my R-12 (I probably have about a pound in it) were to somehow find its way out of my system without using a vacuum pump, how would that affect properly converting the system to R-134 later on? I wouldn't recharge with R-12 and would hope to convert once I get the truck put back together.

Reason I ask, before I knew anything about R-12 I saw someone do the same thing, just hit the air valve until it stopped hissing out R-12... he then used one of the R-134 conversion kits and now he's complaining his a/c doesn't work half as good as before. Wondering if it's because he didn't properly evacuate it or maybe he screwed something up in the conversion.

J wrote:

The system needs to be evacuated (oil and air) prior to being filled. The system needs to be under vacuum before the refrigerant is introduced so the air that's in there at normal atmospheric pressure isn't taking up the space of the refrigerant.

So, regardless if you blow the gas out in yer' garage or take it to a shop, she needs to be evacuated prior to refill. I'd also suggest switching the accumulator out to one that's designed for R-134a. The difference isn't how the gas was removed, it's whether the system was under vacuum when you charged it.

Your buddy's system now stinks for several reasons: system was open for too long to the atmosphere and the accumulator is all plugged up (contains a potent dessicant, can't be exposed to atmospheric air for more than a few minutes before the performance decreases), system not placed under vacuum prior to refill.

Doc

Doc is absolutely right, after you put it back together put a new accumulator on a put a vacuum pump on it for at least 45 min. the shut your gauge valves (if you have gauges) and shut the pump down and watch it for 30 to 45 min. to see if you lose your vacuum, that will tell if your system is tight(no leaks) then add your oil charge and R134A, oh also I would replace the orifice tube also, the variable ones are pretty high but well worth it because the 134 will cool better when driving in the city.

It's because he didn't evacuate it properly.

When he evacuated without pulling vacum, he let atmospheric pressure in.

His entire system is now FUBAR.

How do you know mang?? He he he he he he eh he

Doc

'cuz I accidentally sent a fanblade through my radiator hose and let it sit- and have been sweating my arse off for the last 3 summers.

Gonna fix it tax time.....