I just tried my A/C today, and it only blew out hot air. I checked the refrigerant level, and it was low. So I filled it up with in specs, according to my guage. The compressor is not cycling at all, and I don't hear or see anything loose or running funny with the clutch. Any ideas?

Thanks in advance.

 

How could you possibly have "filled it to specs" when the compressor isn't even running? Not possible without highly specialized equipment.

What is your static pressure (and the ambient temp at which the pressure reading was taken)? If less than 45 psi, the charge is too low.

Steve

 

Did you try jumping your low pressure switch on the dryer? Are you using one of those cans that has the guage with green, yellow, and red zones?

 

The gauge I am using is one that is on the can. The pressure was around 20 psi, which is low. I thought I filled it, but I am an idiot. I didn't even think about the fact that the compressor needs to be operating to pull the refrigerant in. I did re-check the pressure, and it was at the same level it was originally, 20 psi. I will look for the low-pressure switch, and jump it out, as soon as it stops raining here.

 

The rain stopped. I jumped the low pressure side, and filled it up. The guage on the can, can't be very accurate. I filled it up to 45 psi, and the compressor would only run for about 1 second. I filled it up with 18oz. of fluid, and the compressor runs for about 7 seconds, and then kicks out. The outcoming air in the cab, is 65 degrees. Should I add more?

 

With the system that low I would be looking for a leak before adding anymore frig.

 

The system is still undercharged as indicated by the compressor short cycling and the lack of cooling.

You can add more, however it will just leak out until you find and repair the leak. Throw some UV dye in there and hit it with a black light.

Normal static system pressure at 80F-90F underhood ambient should be somewhere around 70-100 psi.

Steve

 

might not need the dye. i had a condenser leak on my old dakota. emptied a whole can in the system. compresser kicked on. im like great its all set, compresser cycled on/off like it should. i shut the hood, look down and there is green refrigerant all over the driveway. i think some brands already have it in there.

 

I added more R-134, and it didn't get any better. I bought real gauges, and the static pressure readings were 35psi low side, and 45psi high side. Yes, the high side number is not a typo. I took a pressure reading after 15 minutes of running the engine, and the low side went to 45 psi, and the high side was at 95psi. I believe the high side should be around 200 psi. Something is way off. I need to equalize the system.
Could this be an orifice tube malfunction? If so, why would it fail? I realize with the system being low to begin with, there is a leak, and I will run dye through it and fix that also.

Any ideas??