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Adding 134a a/c

i had to add 134a to my a/c unit.i was told i must have a leak because you should not have to add any 134a to the car than what came with it when i bought it.is that true? 2002 montecarlo ss 44.000 miles.the a/c is working now any comments thanks bob

There is a EPA allowable leakage spec for 134a. It is very low. I have been googling and checking my reference books for the spec. not comming up with the value,just specs on recovery machines. Time for accumulator replacement (accumulators have a bag of silica (dessicant)that absorbs harmful moisture.Now to you,you lost cooling ability? thats why you new it needed a charge? It depends on how much you had to add to tell you if its allowable leakage or something that needs investigation. Some people dont mind adding 134a every season and could care less about finding a leak,removing moisture from system,replacing accumulator.or proper charge weight.

15% per year, the link you’re looking for is on : http://www.epa.gov/ozone//title6/608/608fact.html#noventing

The car is close to 7 years old and some leakage from the system is to be expected. With age, an auto system will leak off a bit. They’re not hermetically sealed like a home A/C unit.
The real question is just how much did you have to add?

Well if you have a glass of water and you have to keep adding more, you have a leak. If you have to add 134 you have a leak. The only question is how much of a leak. I have a 2002 car and if I had to add, I would want to try and find that leak before I had any added. There is no one always right for everyone answer.

I have only had to add to one of my cars and I had them find the leak for that one. It turned out to be a metal tube that had been vibrating against another part when idling.

Car A/C systems ARE hermetically sealed (which just means totally sealed against atmosphere), but with the vibration, flexing, and harsh environment overall that they experience, they just don’t last nearly as long as a home A/C system without troubles. Well, 134a is pretty cheap by today’s standards and not (quite) as damaging to the environment as R12 was. If it only leaks enough to need topping off once or twice a year, I’d keep topping it off till it gets worse. Around here you can get a can of R134a for about $6. I wouldn’t worry about replacing anything or using “oil charge” right now. Overcharging, especially with too much oil, is pretty harsh on an AC system. And don’t use any leak sealer–those things just gum up the system. If you can deal with topping it off once or twice a year, I’d just do that. It’s a lot cheaper than a total fix and should keep you cool. I’ve been topping off my 94’ for the last 4 years or so. If you’re going to keep the car for more than a couple years, then maybe fix it, otherwise I’d just keep refilling it IMHO. If you’re worried about the leak, many shops will ‘shoot it up’ with a leak detector for free, which shows up in daylight or especially under a black light—usually green or purple. Or you can look for signs of oil on A/C lines–the escaping refrigerant takes some oil with it and usually leaves a little oil, which also binds dust and dirt to it. If it only leaks a little though, you can probably get away with topping it off for years.

i put the 134a in a month ago.the a/c is working fine.that was the first time i put the134a in this car.it cost 20dollars for 19oz of 134a.i really dont no to much about the ac system to fix a leak.what about that leak seallant they sell.for the a/c.or will that do more harm than good.and just like you said the cost for a mechanic to fix a leak is outrageaous.thanks for the advice

scudder i was just on that web site you posted.really great info