DIY A/C recharging opinions?

Recently, my A/C has been blowing just barely cool air. I'm thinking of trying a recharging kit before taking it in for service. My research tells me to stay away from anything that contains a leak sealer because it gunks up the system and could damage the mechanic's equipment if and when I have to have a pro fix it.

My question is whether it's even worth spending $30-$50 for a kit to buy a little time, but money is tight right now and it's still in the 90s. Has anyone got experience with going this route? Any product recommendations or specific ones to avoid?

 

Save your cash and take it to a shop. Without putting a vacuum on the system you won't know if it's leaking and your new refrigerant could all leak out again. You will also put air in the system and your a/c compressor won't like that.

That being said, if you can find the recharge kit cheap give it a try. It may be enough to get you through the summer.

 

Go to walmart, buy the recharge kit there. Use it. I have done this a few times with different cars. They have gauges on them and instructions so you can do it correctly. The meter will tell you when to stop. You can also buy some with die that shows if it is leaking.

 

I agree with wlmuncy. My last truck had a very small leak. I took it to the dealership to have it fixed and payed extra to have a dye put in since they couldn't find the leak. A few months later I took it back and they still couldn't identify it since not enough leaked out. I didn't have to recharge it myself again for 3 or 4 years.

 

my buddy owns a tire service center, and offered to service and recharge my AC for 200 dollars. I bought the 30 dollar can at NAPA, and presto... Good as new. for me, its worth a shot.

 

It sounds like a no-brainer to try the cheap way out first. I imagine there must be a leak somewhere. If the recharge lasts for a few months that will be good enough I guess.

 

To play devils advocate: There is a lot more to AC recharging besides connecting the can and charging to XX amount of pressure. You could actually do more damage than good.

My opinion is: No, I would get it done by someone that knows what they are doing.

 

I got the recharging kit today at O'Reilly's for just under $30. The initial pressure reading was under 20psi and the vent air temp was 74 deg. I put in one 12 oz. can of R134a and the pressure was up to almost 55psi (on a 90 deg day). The vent air temp is now 38.5 degrees! Hopefully it holds for a while.

 

i had mixed results. my old '03 xterra had an ac leak and the first rechargebworked for a while but kept needing refills. i did the dye stuff and found that i had a bad hose crimp on the high pressure side and with the black/uv light thingy could see it. ultimately i had to seek pro help, but at least I knew exactly what the problem was.

 

first get it checked for a leak. I had an old car that was leaking out of the condenser, basically one of the lines right at the top of the condenser was rubbing on something so it sprung a leak.

Got the leak fixed and used one of those DIY recharge kits and it worked great. If your AC needs a recharge it means that there is a leak somewhere. It might be a very slow leak and I suppose you could get away with just doing a recharge every year, but would be best to find and fix the leak.

 

The A/C on my old '92 went kaput, and I ran through my stash of R12, so I got a new car and kept the truck for hauling stuff. I didn't like driving a car, so I got a new Tacoma after a few years and didn't need 2 trucks. I used a conversion kit with a sealer just to get it working somewhat before I sold it. The gauge wasn't showing a measureable loss of pressure after a couple of weeks, and it wouldn't hold an R12 charge for that long before. A month later and it was still freezing cold, one of the potential buyers had me turn it off because it was too cold!

I'm not sure how long it lasted after that since I sold it and it headed to Mexico, but depending on the situation, it can be worth a shot to even try the sealer. Many times leaks are hard to find, and you can end up spending a LOT of money replacing different parts until you find the leak. I wasn't about to spend a grand on an old truck.

 

The problem with those charge cans like that is you do not know how much of the original pressure is just pressurized air. A leak can not only leak out the refrigerant (and the lubricating oil) but it also allows in air. This air will make a needle on the gauge LOOK like the pressure is good, but in actuality the charge level is still low, and the air that has been drawn in will quickly start to corrode. Best thing to do is get a leaking system checked out and fixed properly.

Glad to see that this temporary fix has worked out for you on this go around. I hope you take it in soon to get it inspected/repaired.

 

if you have a small leak (like over the course of years ) and if there is still pressure in the system you are good, just get a recharge kit (ac pro works well, i have used it). if you have refer pressure over atmospheric pressure there will be no air in the system, maybe moisture(problem).

if its a large leak and totally no pressure you will have to take it in to be leak checked, fixed, vacuum, and charged.

i do industrial HVACR for a living.

 

What he said. That leak will show its face again and with a vengence. If you cannot find the leak under the hood, get ready for the worse (condenser). I invested in professional gauges, a neumatic vacuum pump and an a charging adapter for R-134 at Harbor Freight. Total I paid less than $100 bucks. I got myself some YouTube lessons on how to evacuate old freon, vacuum and re-charge and presto! Now I don't have to bend over to the shops.

 

Respectfully I have to disagree with you. I have seen MANY times a system that had a leak where the base pressure in the system showed there to be close to 1.5 lbs of R134a, when in actuality, after evacuating the system there was less than a tenth of a pound. Now I am not going to say I am the perfect auto AC tech, but I have been doing this for over 20 years now. I see no other explanation for this pressure other than air being drawn in once the R134a has been leaked out. At this point the compressor would be trying to pull a vacuum when engaged, thus drawing in residual air, and giving a false indication of R134a levels. It was one of the things we learned about the automotive systems in HVAC training.

 

I should probably qualify my previous post. My experience was with an old R12 system that would have to be totally reworked, and I was selling the truck. It was worth it to give it a shot with a cheap conversion kit (and I informed potential buyers that it had been broken but was converted recently). It worked great in my case, but obviously not a perfect fix and would probably only last 1 season.

Once again, Bama knows his stuff, take his advice. Adding a can is a temporary fix and it will only get worse -- and possibly be more expensive to fix properly.

 

my brother just put his second charge into his older dodge. it works. he is too lazy to find the leak and doesn't much care.

I would never ever charge a system without the proper manifold gauge set at the very least. if you take it to a professional, you will never have to worry again. your leak will be fixed, the system will be evacuated, and refilled to spec.

to my knowledge, (I work for a refer company, but only run piping) a pressure gauge to fill a system is irrelevant unless you know temperature/pressure relationships to 134a. the system charge is a specific weight of refrigerant- if you are guessing by a pressure guage, it will be underfilled under hot conditions and overfilled under cold conditions. the only correct way to charge is to evacuate, find the leak, and start again.

of course, if you use the store-bought can and charge "to the green", it will be correct, assuming that your a/c will always be operated under those conditions(temperature) and you don't lose any refrigerant.

 

Exactly correct. I have a conversion table printed out on the office wall that shows what the proper static pressure should be for any given system. The good part is that it does not require knowing how MUCH R134a is supposed to be in the system since it uses static pressure. Simply hook up the gauges, compare the static pressure as well as humidity and ambient temperature to the chart and you can tell if the charge is correct. Unfortunately as I said earlier it all depends on if there is a leak and the pressure eventually dropped down low enough to draw in outside air. THEN the pressures will be incorrect at static. So a secondary check you have to make is operating pressures, and if the gauges show a proper charge at static, but when running the pressures are equally off, then you know that there is air in the lines.

 

Wanted to chime in in case anyone is searching threads, not many have been updated.

My 2007 was bought with 57,000 miles and A/C ran out within 5,000 miles of my owning it. Where I live, A/C isn't even a thing in many homes. We have 8 month winters, essentially. But summer gets hot and I get older, and it was time to just try to fix it. I went cheap easy option first.

A/C Pro Recharge bottle from WalMart. I read all the instructions first and recommend it. Its and easy job, but you can step on your own toes if you get ahead of the steps or if the engine isn't warmed up and A?C on to check initial charge.

70 days in with daily use in the afternoons for 35 minutes and it is ICE COLD. Rear ventilaltion in the DCSB isnt great, but my pup seems to be happier back there.

Ask away if anyone has questions, but I say just go for it if you're questioning things. Make sure you buy the non-sealant version.

 

Orielys will let you rent the vacuum pump and gauges for free. That and this video made it super simple.
https://youtu.be/Pdq8JAlct6s