I almost over charged my ac

[Wizard]

I put in the first can and it didn't charge my account enough. Then my house mate gave me an old bottle of refridgerant. At first I thought it wasn't working or too old because the gage never changed. So I went and bought a new 2nd bottle. When I put the new pressure gage on it shot up to right on the line between just enough and too much. Now my car makes a few short hissing sounds like it's releasing pressure for a few minutes after I start her up. What's the consequences of over charging? Just curious what I almost did to my car/ maybe already did.

[DaveT]

At best, makes the compressor work too hard. Bleed some of the exceas out.

[matt167]

little Too much might not hurt but actually  makes the system less efficient . Way to much runs the chance of liquid refrigerant getting to the compressor and locking it up

 

 

Really depends on how much too much

[golucky66]

Imo, get it check out by a certified professional before you possibly cause more harm then good.

Edited June 19, 2017 by golucky66

[Wizard]

So now when my ac is on my car lurches just a little bit you almost don't feel it but it's there. I let some pressure off but it's still happening. It's also making quick hissing noises like it's letting off pressure.

[idosubaru]

Why don't you get the right pressure in there and let some out?

 

You didn't almost do anything. The system shuts off the AC when the refrigerant isn't doing what it's supposed to be doing. Undercharged - compressor turns off. Overcharged - compressor turns off. It will cycle on and off while running as the pressures dynamically change all the time. No big deal.

 

Overcharging could lead to dramatic compressor failure, if the compessor ingests any refrigerant in a liquid state. if it tries to compress liquid something will break and may not be in small fashion thanks to liquid not being compressible. I'm not familiar with how likely that is because its so rare, it doesn't really happen. I doubt you'll see that or anyone else has unless someone tried to flippantly bypass pressure switches.

 

A completely empty system can run on two bottles. attaching bottle after bottle to what may have been a vehicle that didn't need any to begin with isn't a good idea.

 

What you need to do is similar properly charge it. If all you have is that cheap store pressure gauge then get it further below the line you're speaking of and bleed some pressure off.

[idosubaru]

The lurching is normal. It's just the a/c compressor clutch turning on and off. They all do this when the pressures aren't right like I described above. Pressure good - compressor clutch engages....pressure bad - clutch disengages....wash rinse repeat.