AC Recharge

I found this guy on craigslist doing charges for 40 bucks, my trucks AC isn't working all that well. Long story short this guy fills my AC and its not very cold so he releases some R12 into the air and puts another can in and still not very cold, all the while I have the truck revving 2 grand, now it was pretty hot here yesterday in T.O. so understandably my temp started to rise. The guy gets a little freaked and says you better get someone to check it out. Anyways he charges me 20 bucks. I drive away the temp goes down and the AC get colder and colder, makes perfect sense to me why this happened, just needed air flow to get things moving. My question is I think he put too much R12 in, his gauge was showing boarder line red, can anything get damaged by having too much R12 in it.

 

Umm I think we use r134a in our trucks. R12 hasn't been used since like the 80s. Besides to do ac service, you have to be certified to do that, anyone can recharge then you overcharge your system and then blow out you orings, then its more expensive in the end. Do it right and have a professional look at it.

 

You cant buy do it your self ac recharging kits at kargen! Saw one the other day. Can remember the name of the poduct off hand

 

My Bad R134a is what he used, So it will blow out the O rings with too much pressure.

 

Yup and replacing them isn't too bad, but time it will take to do it, plus labor charge, it will come out more expensive. There are recharge kits at auto parts stores, but you have to keep in mind that you have to know the capacity of the ac system, some kits already come with a hose and pressure gauge, but if you put the right amount in, and still getting warm air, you have another problem. Its just safer to have some one look at it who's not gonna blow up your compressor.

 

Which O rings are we talking about, the ones on the canister where the 2 lines connect behind the front grill

 

Did he vacuum out the entire system??

The proper way to recharge a system when the AC is not working is that you need a pump to evac the entire system. Hold the system under negative pressure for 10+ minutes and see if it changes, if it changes you have a leak. This is a fundamental start.. Did you put oil in the system? You are suppose to add little amount of oil in the system also Overcharging is bad it can blow the seals in the compressor pump and in the lines causing a headache to find out where the leaks are..

 

Exactly, theres a proper way of doing it, and any monkey can charge a system. I have people come in and buy a can of r134a and put it in right out in the parking lot. we can't help either, nor can we tell people how to put it in. If you or someone else screws it up, its on you. Like I said before, take it some place thats certified and avoid a headache all together. my .02

 

Overcharging a system decreases capacity and raises pressure, putting stress on the compressor and diminishing the systems ability to reject heat. If you pull a system into a vacuum that has a leak without FIRST checking for a leak you will pull air and moisture into your system that will ALSO damage it. It is bad practice to check for leaks by pulling a vacuum. I suggest charging the system properly with R-134a and testing possible leak points (hose connections and joints) with soap-bubble leak-reactant you can purchase at any hardware store.

More than likely, performing any maintenance aside from changing your cabin filter and keeping your condenser coil clean is a terrible idea if you have no experience or knowledge.

Also, releasing R-134a into the atmosphere like this guy did is also against the law, and you can be fined up to $25,000 for doing so.

 

When should you have it recharged anyways? Like every 4-5 years or what, or when it doesn't fell as cold?

 

Its a closed system, like your refrigerator. Ideally, it should never need to be recharged. Things bouncing around like they tend to in an automobile will cause some leaks though, as to why the above mentioned negative pressure test should be preformed before just refilling it.

Generally, if its cold enough for you, its fine. If its not (and things are working), you've lost some freon along the way and need your system properly checked so you aren't just dumping it in the air.

 

My air is cold but needs a little 134 added. What should my manifold gauges read when it's at capacity? I also have the cheap auto zone gauge but it's not specific enough. I want to know at what psi on the low side is the right amount. It's blowing 50 degrees on the dot so I guess that's good enough. I know climate has a lot to do with it.

 

I don't know if 134a is different than r12 in molecule size, but back in the day I read that r12 could migrate through the rubber hoses under pressure over time, a small amount, but still would need a refill eventually over time if the system didn't grenade first over time.
Commercial and residential ac's have hard pipe/tubing, so no loss should happen unless they did a crappy soldering job.

 

It seems that my AC is not performing like it did when I bought the truck. Seems as though the air coming out of the vents is not as cold as it was 20 years ago, but what do I know...

Not sure if I should take it to an AC specialist - $$ are kinda tight right now. I do drive many of the forest roads in Nevada and Utah, and the truck has been subjected to bumps and vibrations. What do you think?

 

Holy thread revival ... 9 years old

 

If you were so bored with this thread, why did you bother to read it in the first place? Guess you had nothing else to do except leave the snide remark...

 

Change the cabin air filter. Clean all the dirt and bugs out from the condenser. If that doesn't help you may need to take it in. Might have a small leak somewhere. 20 years is a long time for rubber hoses, they may all need to be replaced in order for the a/c to run for another 20 lol

 

Also if your truck has a fan clutch, check your fan clutch. If the engine fan isn't spinning as fast as it should, it will cause the a/c to be warmer.

 

I did a lot of research on AC systems and how to properly recharge them. The video below is pretty damn long but I believe you'll find it very informative if you're interested in being able to service the AC system on your 1st Gen.

https://www.youtube.com/embed/zlRE0Zeeyrc

 

the high pressure can be from too much refriderant or a blockage in the system, expansion valve, condensor etc.