Can i Re-Charge the AC myself?

[Andyjo]

So the other day, it got hot out, really hot, and i go to turn on my AC, and nothing happens.. just hot air blowing in my face. I figured that it hadn't been turned on in a while, i should just let it go for a while... nothing.. just hot air.

I'm guessing it just needs to be recharged, i've never done it before, and don't know if you can do it... without going to a shop that is.

Has anyone done this before? without having to deal w/ mechanics finding other stuff to fix

[Spokane-Pete]

What year model is it? Does it use R12 or R134a Freon? Do you have any test equipment, or can borrow some? Have you checked fuses and see if the compressor is even turning? Might be electrical rather than low freon.

 

Peter S

[ericem]

I also have the same prob with my 93 legacy but i was thinking of using 414b instead of the r12 refrigerant. Has anyone acually don this sucessfully?

[Andyjo]

What year model is it? Does it use R12 or R134a Freon? Do you have any test equipment, or can borrow some? Have you checked fuses and see if the compressor is even turning? Might be electrical rather than low freon.

 

Peter S

 

97 OBS, I don't have any testing stuff, i MIGHT be able to borrow some, and i'll check the fuses in a bit.

[dpoppeli]

I'm no expert but here's what I've found: compressor will not turn on/off when sensing low refrigerant pressure. Easiest way to try a fix is to try and charge the circuit. This year car probably takes 134A. Costs about $7 a can at Kmart or wherever. Also need to buy the piercing vavle+hose ($15?). Just screw this onto the low press side (the only valve of correct size) and screw it on. Some teflon tape on threads of the car and can seem to help prevent wasting the stuff. You can use a gage and refeernce a service manual (Haynes publishes a general auto regrigerant manual) as well but I just turn the car on, AC to high, and turn the can upside down until the compressor starts cycling again and cold air starts blasting. You can stick a temp gage in the vents to see what you're getting. Should be in the 50's. I've put some of the stop-leak junk in older cars and it's worked great - I'd hate to do this on anything you really like.

 

 

So the other day, it got hot out, really hot, and i go to turn on my AC, and nothing happens.. just hot air blowing in my face. I figured that it hadn't been turned on in a while, i should just let it go for a while... nothing.. just hot air.

I'm guessing it just needs to be recharged, i've never done it before, and don't know if you can do it... without going to a shop that is.

Has anyone done this before? without having to deal w/ mechanics finding other stuff to fix

[idosubaru]

yes you can. i do it. i have a 97 OBS too and though i've never touched the AC i did notice it appeared to be R134 fittings which will be much easier for you to deal with.

 

most likely if this just started you should have a decent charge on the system with minimal if any air entering the lines. so i would just charge. before you go messing with it though, pull the caps off (if there are any) and have a look at the high and low pressure ports. inside you'll see a schrader valve (just like in a tire valve stem), these are the most common leakage points as they have a very tiny oring at their base. a leak will be noticeable by wetness and possibly even bubbling if any oil comes out, typically it's really easy to notice which is why i say to check. even if you don't want to fix it, it would be good to know for future reference as the valves cost like 50 cents and the valve removal tool costs like 2 dollars. problem is you have to discharge the system to replace them...unless you buy a slightly more expensive a/c tool that actually allows you to pull the valve and replace it with a new one without discharging the system. have to look them up, forget what they are called, but it's a smooth little device. of course a shop should do this for you for like 10 bucks since they have the tool and valves sitting around, but they won't. they'll say it needs leak tested, valves replaced, vacuum pulled, recharged and 250 dollars later your a/c works when i would have just replaced the valve for 50 cents. sometimes you can tighten them up to slow the leak (needle nose pliers will even work if yo'ure careful), but that's hit or miss usually the oring is too degraded at that point. soap on the valves will help show a leak if you don't see anything.

 

would be best to buy a hose with a gauge on it if you don't have a manifold set of gauges for doing it "the right way". you don't need these, but they are nice, it's another thing to learn figuring them out. i'm not going to cover that now. anyway, you can get a small hose with a gauge on it and it might even come with directions. get a decent hose with metal fittings and stuff, not the cheap plastic ones as they break and suck. the right hose can serve two purposes - you can attach it to your A/C and close the valve so you just get a pressure reading. and you can attach a can of refrigerant to it and open the valve to charge your system. that's the kind of hose you want. some of the cheap hoses have no valve so when you're done charging the refrigerant just expels into the air.

 

here's the bottom line..finally you say, attach the can to the hose, hose to the car and charge away. it's really that simple. keep it charged so no air gets in the system. air and humidity (water) will cause corrossion internally and eventually your compressor will seize.

 

you can make it complicated by using a vacuum pulley and gauges and all that jazz...depends what you want to do, that's actually easy as well if you have the right tools.

[Legacy777]

The r134a systems, you should be able to add refrigerant yourself.

 

Unless you can get a hold of R12, you'll have to take it somewhere, or convert it to 134a. I've got a write up on here. I wouldn't recommend mixing refrigerents. Never heard of 414b.