decided to take ac unit in to test it. Thought I would share my experience, as before he even tested it he told me its fubar. I asked how he knew this and he said he could tell I tried to recharge it from one of those pep boy cans.. I called bs and asked him to test it anyway even thought he said both font and rear seals are gone etc. We tested it and he was totally correct both seals leaking. He said this happens all the time and people should never use those as they ruin the compressor. I did not believe him so,I asked my service manager and he confirmed that all though they do not ruin the compressor automaticaly they can if you do not know what you are doing. I thought i did but obviously not. Basically you over fill it without knowing this and it ruins the compressor. If any other specialist know more please feel free to elaborate.
So when I serviced my cars, I empty the system, and then fill it to 2.2 lbs and stop. Never had a problem.
That is the only way to do it. I know it is tempting to "just add freon" but modern car, home and commercial HVAC systems all charge the system based on weight not pressure. Buy adding more pressure you can run the risk of blowing seals and ruining the compressor. You need more gear today than the old days. Gauges, scale, recovery/vacuum pump and recycling container. We used to be able to charge residential systems by determining the superheat and supercool temps but that is out the window as well with mini split systems. The only process that is acceptable is to: Check for leaks, evacuate the system, charge the system with the correct amount (weight) of Freon and check for leaks again.
Correct answer^^^^^^^^^^ I seen so many dryers that are clogged from the crap napa-pep boys sell as home remedy's
Basically they said I put too much in. The cans only have a pressure not a weight I believe. Originally this is what happened When I took it in they evacuated it, checked for leaks, then it leaked so I took it home and tightened fittings, took back they checked it and it held so they filled it. 2 years go by and not working very well so I add 134a from a can and likely wreck it. Worked ok for about a month Should have taken it in again is the moral of the story. Just wanted to confirm and let others know so they do not cheap out and do do what I do
Overncharge even though I did not put in over the green area in the pressure gauge that comes with it.
Yes this is the laymens proper,way we shood all use if diy. The techs proper way would be use the machine and it empties, creates a vacume to check for leaks, then fills and adds corrthe ct amount of oil
I would have never done this except a fri nd helped me do this to a jeep I was selling and it seemed like it worked and was easy ther fore I thought I knew what I was doing. Obviously not so that is why I shared it. Just because it works for now does not make it correct. I wrongly then assumed for the last 3 years the lines were leaking when in fact I had blown the seals in the compressor.
Grant, I appreciate your post. 7 out of 10 times you can get away with a "134a gauge can" and it will solve the problem......for a while. Your friend's Jeep is a good example if you are trying to quick fix something to sell it and let the next owner pay for fixing it. What happens is the old Freon went someplace and without addressing the leak.....the new Freon will also leave the system. When you use a gauge can....you are pressurizing the low side of the system. While pressures vary by system and temperature, the can has more pressure than the system can handle. If too much pressure enters the low side....the seals will leak/fail making the problem worse. In your case, I'm willing to bet your seals on the compressor were already compromised and leaking before you added Freon. Since your system wasn't cooling to begin with....the original Freon either exited through the compressor seals or a leaking hose. So, while it true you spent $10 on a 134a gauge can and a lot of money on rebuilding and properly charging the system......you can take some comfort that the car was headed in that direction for a while. Every time you do an engine out service you have to evacuate the systems and open the lines. If this isn't done properly.....it is only a matter of time for a problem to show up. I haven't seen a "go-no-go" evacuating/charging machine but that doesn't surprise me. I have EPA licenses to buy R-22, R-12 and R-410a. The EPA is very specific about Rules and Laws that govern Freon service. I think it is a bit silly to rely on a machine to figure out if a system is ready but that is where we are headed.
Sounds like big brother SnapOn making it foolproff for us I just got a new recovery system thats pretty sweet It can use several gases as long as I go through the proper purge process, professional grade not that auto bells whistle thingy. A guy at work made a vacuum pump from an industrial pimp and pulled too much vacuum, sucked the compressor backwards, was too funny. The pump was huge not for ac use LOL
In any AC system high side and low side pressures depend on ambient temperature. Image Unavailable, Please Login
