I posted this in a thread, but realized that it's something that everyone should know.
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If you AC system comes on but does not blow cold air:
You should put a pressure tester on first before adding anything.
If you have pressure, then you don't have a leak. If you have no pressure, DO NOT ADD R134a!
If you have zero pressure, place a vacuum pump on it. Take it to -30 in Hg. Remove the pump. If it keeps a vacuum after 30 minutes or so, it should be good. If it creeps up, you have a leak and need to find the leak.
If you have have a slow leak, most of the cans with stop leak will work. If the gauge moves up faster than a creep, then you have a large leak and you'll have to find the leak and repair it first.
If you have to open your system, you need to replace your AC drier. This is what absorbs any water in the system. Water mixed with the R134a/oil causes an acid which will start eating up the internals of your AC system, causing more problems. Since the system is open, you might as well replace any parts that need replaced. Once you repairs are done, you need to vacuum it to -30 in Hg again.
If it holds a vacuum, then you can add the R134a in. If not, back to the beginning to find the leak.
Now, I only say this if you have ZERO pressure and all your freon has leaked out. If you still have pressure, you should go to an authorized service center and have them recover the R134a before any work is done. A lot of service centers won't even work on your system if you added stop leak for fear it will mess up their equipment. Will it? I don't know, I've read both arguements, but most places want to know if you added stop leak.
If you buy a vacuum pump, get a real pump, not one of the Harbor Freight venturi pumps. You need to get the system to -30 in Hg.
Hope this helps.
Hardwarz
*********************
If you AC system comes on but does not blow cold air:
You should put a pressure tester on first before adding anything.
If you have pressure, then you don't have a leak. If you have no pressure, DO NOT ADD R134a!
If you have zero pressure, place a vacuum pump on it. Take it to -30 in Hg. Remove the pump. If it keeps a vacuum after 30 minutes or so, it should be good. If it creeps up, you have a leak and need to find the leak.
If you have have a slow leak, most of the cans with stop leak will work. If the gauge moves up faster than a creep, then you have a large leak and you'll have to find the leak and repair it first.
If you have to open your system, you need to replace your AC drier. This is what absorbs any water in the system. Water mixed with the R134a/oil causes an acid which will start eating up the internals of your AC system, causing more problems. Since the system is open, you might as well replace any parts that need replaced. Once you repairs are done, you need to vacuum it to -30 in Hg again.
If it holds a vacuum, then you can add the R134a in. If not, back to the beginning to find the leak.
Now, I only say this if you have ZERO pressure and all your freon has leaked out. If you still have pressure, you should go to an authorized service center and have them recover the R134a before any work is done. A lot of service centers won't even work on your system if you added stop leak for fear it will mess up their equipment. Will it? I don't know, I've read both arguements, but most places want to know if you added stop leak.
If you buy a vacuum pump, get a real pump, not one of the Harbor Freight venturi pumps. You need to get the system to -30 in Hg.
Hope this helps.
Hardwarz
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