Need some AC Help

[Kriegen]

Having a bit of problem with my AC. It worked excellent back in the summer but now it's not putting out any cold air and when on Max AC, the compressor cycles on and off every 5 seconds or so. I've checked the pressure on the low side with an idiot gauge(colors that show undercharged, properly charged, over charged, about to blow up...) When the compressor cycles, the pressure gauge will change from being at the top of properly charged to the bottom of properly charged but always in the range of properly charged.

any suggestions?

Thanks

 

[1AJeremyD]

What gauge are you actually using to check everything out? Are you using the one on the can?

 

[Kriegen]

Basically yeah the one on the can

 

[1AJeremyD]

I wouldn't really say that the can one is a good way to test your system. I don't know if autozone rents the ones that you hook up to the high and low side but I would see they it is available and hook it up to test it out. There is one thing that I will say, if you charged the system with one of those cans, they normally come with some sort of leak stop in them. Problem with that is it can clog up the system and not allow proper flow throughout the whole system. I would probably bring it to a mechanic to have them check it out. Whatever the problem is. It might not be cheap.

Second thought on the whole issue. Did you hear a noise inside the panel when you switched from the heater to the a/c? there is a door that should flap over to the evaporator side of the HVAC system. Just a second thought in the whole matter

 

[Kriegen]

Blend door is definitely not the issue. Have no problems with getting heat or cool air, just no AC air.

 

[1AJeremyD]

Ok great. Figure I would at least rule that out. I would say have it properly pressure tested then. That stop leak stuff gums up a lot of A/C systems

 

[Kriegen]

I haven't actually put any of the stuff in, just used the gauge from one I've had for a while. It is a lack of pressure though, I jumpered the low pressure switch with the gauge on and it dropped all the way down. So basically when the compressor starts up, the pressure drops too low and the low pressure switch opens and shuts the compressor off. I just wasn't seeing it drop in the gauge because once the compressor turned off, the pressure stopped dropping.

 

[ranger7ltr]

You really need a proper gauge set...

to determine the actual charge in your system...And technically R134a should not be "topped off" like R12 could be thanks to its molecular structure...

Not that folks don't top the charge off but it is so difficult to get the proper charge level in a system and not overcharge it...

If you have enough charge to close the low pressure switch to run the compressor yet not get any cool air you are quite a bit undercharged especially if the compressor is being kicked off by the low pressure switch every 5 seconds...

Plus finding that refrigerant leak will help you not have to do this again next season or later this season depending on the level of the leak...