Recharging AC, can I do it myself or do I need to
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You could do it yourself, but the best way is to have a professional do it. First of all, why do you need to have it recharged? If it's low on refrigerant, you have a leak. You need to fix the leak first, or else you'll need to recharge it again soon.
Second of all, unless the system is completely empty, you don't know exactly how much refrigerant is still in the system. Therefore, there's no way to know exactly how much refrigerant to add back in. A shop would take the remaining refrigerant out to start fresh, then add the proper amount.
Third of all, pretty much all of those recharge kits have some kind of stop-leak and/or conditioner and/or some gimmicky "booster" that supposedly cools better. All of that is junk and can cause problems. I would just use pure refrigerant without any of that. The recharge kits also have only a cheap, inaccurate low side pressure gauge. You're much better off using a real manifold gauge set with accurate low AND high side gauges, and you can connect it to a can of real, pure refrigerant.
Second of all, unless the system is completely empty, you don't know exactly how much refrigerant is still in the system. Therefore, there's no way to know exactly how much refrigerant to add back in. A shop would take the remaining refrigerant out to start fresh, then add the proper amount.
Third of all, pretty much all of those recharge kits have some kind of stop-leak and/or conditioner and/or some gimmicky "booster" that supposedly cools better. All of that is junk and can cause problems. I would just use pure refrigerant without any of that. The recharge kits also have only a cheap, inaccurate low side pressure gauge. You're much better off using a real manifold gauge set with accurate low AND high side gauges, and you can connect it to a can of real, pure refrigerant.
If the system is still full, but low, you should be able to charge it yourself. If a part has been replaced or there was a leak, you will most likely need to have it done unless you have your own electric vacuum pump to evacuate the system. In California there is a $10 core charge on the R134 bottle, and I think you have to return it in 90 days whether it is empty or not. I suggest getting an AC pressure gauge first (@ Walmart) to see it your system is low. If it isn't, don't bother recharging it.
Originally Posted By: exranger06
First of all, why do you need to have it recharged? If it's low on refrigerant, you have a leak. You need to fix the leak first, or else you'll need to recharge it again soon.
THIS is the #1 misunderstanding about air conditioning. I always hear people say 'oh, it just needs to be charged', like its a battery.
First of all, why do you need to have it recharged? If it's low on refrigerant, you have a leak. You need to fix the leak first, or else you'll need to recharge it again soon.
THIS is the #1 misunderstanding about air conditioning. I always hear people say 'oh, it just needs to be charged', like its a battery.
The charger kits are a risk. Not only to overfilling/over pressurizing the system, but incorrect compressor oil levels. It can be done, just make sure you have the correct numbers, dont go by the "green" on the gauge they give you. If you use one of those charger kits and the pressure is what its supposed to be STOP! Don't even use it.
JHZR2
Staff member
It's doable but you need good gauges, need to get air out of lines, etc.
If static pressure went too low the system must be opened, r/d replaced, 500 micron vacuum pulled, etc.
If static pressure went too low the system must be opened, r/d replaced, 500 micron vacuum pulled, etc.
Originally Posted By: mpvue
Originally Posted By: exranger06
First of all, why do you need to have it recharged? If it's low on refrigerant, you have a leak. You need to fix the leak first, or else you'll need to recharge it again soon.
THIS is the #1 misunderstanding about air conditioning. I always hear people say 'oh, it just needs to be charged', like its a battery.
Then how can I make my AC colder? How do I know if it needs to be recharged?
Originally Posted By: exranger06
First of all, why do you need to have it recharged? If it's low on refrigerant, you have a leak. You need to fix the leak first, or else you'll need to recharge it again soon.
THIS is the #1 misunderstanding about air conditioning. I always hear people say 'oh, it just needs to be charged', like its a battery.
Then how can I make my AC colder? How do I know if it needs to be recharged?
Originally Posted By: 7055
Then how can I make my AC colder? How do I know if it needs to be recharged?
Well, the thing you should NOT do is just assume it needs a recharge and just blindly add refrigerant. You need to hook up a manifold gauge set and see what the pressures are and see if they're in spec. I have the Haynes AC book in .pdf format. It has a good troubleshooting section and lots of other good stuff. I can email you a copy if you'd like.
Then how can I make my AC colder? How do I know if it needs to be recharged?
Well, the thing you should NOT do is just assume it needs a recharge and just blindly add refrigerant. You need to hook up a manifold gauge set and see what the pressures are and see if they're in spec. I have the Haynes AC book in .pdf format. It has a good troubleshooting section and lots of other good stuff. I can email you a copy if you'd like.
One big problem is that many people do not purge the hoses and get air into the system.
I recommend that you have the system checked by a professional who has the proper tools and experience.
I recommend that you have the system checked by a professional who has the proper tools and experience.
JHZR2
Staff member
Originally Posted By: SrDriver
One big problem is that many people do not purge the hoses and get air into the system.
I recommend that you have the system checked by a professional who has the proper tools and experience.
It's very true. I always keep some pressure in my gauges when removing them, so I do t have air in them. Not sure if this is the best approach, but I suppose it works. If I connect to a bottle I purge that side too.
One big problem is that many people do not purge the hoses and get air into the system.
I recommend that you have the system checked by a professional who has the proper tools and experience.
It's very true. I always keep some pressure in my gauges when removing them, so I do t have air in them. Not sure if this is the best approach, but I suppose it works. If I connect to a bottle I purge that side too.
Originally Posted By: 7055
Originally Posted By: mpvue
Originally Posted By: exranger06
First of all, why do you need to have it recharged? If it's low on refrigerant, you have a leak. You need to fix the leak first, or else you'll need to recharge it again soon.
THIS is the #1 misunderstanding about air conditioning. I always hear people say 'oh, it just needs to be charged', like its a battery.
Then how can I make my AC colder? How do I know if it needs to be recharged?
Firstly go through the venting system, look for ducks that came loose, obstructions. Then verify the vents are closing to outside air correctly. If you have a cabin air filter change that. Then lastly would be the charge.
Originally Posted By: mpvue
Originally Posted By: exranger06
First of all, why do you need to have it recharged? If it's low on refrigerant, you have a leak. You need to fix the leak first, or else you'll need to recharge it again soon.
THIS is the #1 misunderstanding about air conditioning. I always hear people say 'oh, it just needs to be charged', like its a battery.
Then how can I make my AC colder? How do I know if it needs to be recharged?
Firstly go through the venting system, look for ducks that came loose, obstructions. Then verify the vents are closing to outside air correctly. If you have a cabin air filter change that. Then lastly would be the charge.
I recharged my Ranger a couple months ago and it is still working fine, perhaps next year it will be empty. I'd have taken it in, but hate the hassle of dropping off and picking up the vehicle. When I got it the AC was basically empty. Was used as a winter vehicle so maybe had rarely been used by previous owner.
Some systems will loose a bit of charge in winter when seals/couplers contract... Been there done that with the mother in laws 23K mi Pontiac Sunbird...
IF the compressor is cycling constantly on a hot day with blower on high, it's likely low on charge, you should be able to add till the cycling stops and be safe... If it isn't short cycling ot starts cycling again after recharge, have a professional check it...
Originally Posted By: Loobed
If the system is still full, but low, you should be able to charge it yourself.
How can a A/C system be full but low???
IF the compressor is cycling constantly on a hot day with blower on high, it's likely low on charge, you should be able to add till the cycling stops and be safe... If it isn't short cycling ot starts cycling again after recharge, have a professional check it...
Originally Posted By: Loobed
If the system is still full, but low, you should be able to charge it yourself.
How can a A/C system be full but low???
a cheap guage that works can work but will only give you low side pressures. you can do it . just be smarter than the guage. if the compressor isnt kicking on and there is power to the system you can assume it need refrigerant . how much who knows. you can get it good with a working low side guage . if the car takes 30 oz to fill it up and you can push the little lowside port and tell there is still some in it fill it until pressures are good. but keep in mind 30 is a complete fill. so dont go over probably 20oz
Does it work ok at speed, then warms up at idle? i'm getting a whole bunch of those cars with dying compressors and those are the symptoms.
Originally Posted By: Chris142
Does it work ok at speed, then warms up at idle? i'm getting a whole bunch of those cars with dying compressors and those are the symptoms.
Yup we replace a lot of compressors on those and the Freestyle / Taurus X that use the same powertrain. They leak out the front seal on the compressor.
Does it work ok at speed, then warms up at idle? i'm getting a whole bunch of those cars with dying compressors and those are the symptoms.
Yup we replace a lot of compressors on those and the Freestyle / Taurus X that use the same powertrain. They leak out the front seal on the compressor.
Originally Posted By: mattd
I would absolutely bring it to a shop. Using the 134a in a can is asking for major issues. They make the expensive A/C machines for a reason.
Yeah for supposedly saving the environment and charging the poor customer a bunch of money...
For years I pumped A/C systems down using a old refrigerator compressor, and recharged them till the pressures looked good... Haven't did one since '03 when the '93 Grand Marquis burned up the compressor(I poured ashes out of it)... The internal fire burned a hole in the low side hose and dumped all the charge... I Repl compressor, all the lines, dryer, etc, flushed the evaporator & condenser, pumped it down with said refrigerator compressor and recharged... That system is still operating fine...
I would absolutely bring it to a shop. Using the 134a in a can is asking for major issues. They make the expensive A/C machines for a reason.
Yeah for supposedly saving the environment and charging the poor customer a bunch of money...
For years I pumped A/C systems down using a old refrigerator compressor, and recharged them till the pressures looked good... Haven't did one since '03 when the '93 Grand Marquis burned up the compressor(I poured ashes out of it)... The internal fire burned a hole in the low side hose and dumped all the charge... I Repl compressor, all the lines, dryer, etc, flushed the evaporator & condenser, pumped it down with said refrigerator compressor and recharged... That system is still operating fine...
It depends on what AC equipment you have and what your knowledge is of how these systems work. I taught myself how to do auto AC work by reading AC books and manuals and going to online AC forums and reading there. I have repaired around 10 vehicles in the 6 years I've been able to do this stuff and saved myself and other people tons of money. I bought most all of the necessary tools to do this stuff except an expensive recovery and recharge machine.
The first vehicle I repaired was one of my 92 Cavaliers that my fiance drives. It was originally an R12 system that I converted to R134a and six years later it still works good. I repaired the systems on my other 92 Cavalier(whick I kept R12), and both of my 98 chevy trucks and all of these still work fine.
The bottom line is most AC repair work is very expensive and if you invest some initial money on the necessary equipment and do some research, you can learn to do this type of stuff. It really is not that difficult.
Wayne
The first vehicle I repaired was one of my 92 Cavaliers that my fiance drives. It was originally an R12 system that I converted to R134a and six years later it still works good. I repaired the systems on my other 92 Cavalier(whick I kept R12), and both of my 98 chevy trucks and all of these still work fine.
The bottom line is most AC repair work is very expensive and if you invest some initial money on the necessary equipment and do some research, you can learn to do this type of stuff. It really is not that difficult.
Wayne
I do all my own automotive A/C work and have never had any problems. Trained myself over time
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