are you sure they evacuated the system properly? If the compressor is running and the ATC shows cooling and not econ, then it sounds like maybe you have too much gas in there or there is a bad component....... Did they change any components when they evacuated the system?

I'm not sure if the systyem was evacuated properly or not. No components were replaced. It appears that the system is pressurized becase when I connect to gauge hose to the low side connection port, ther gauge reads in the yellow, at about 50 PSI.
Is the high side port used for evacuating the system? Not that I want to try this myself, but I was curious what the high side connection is used for.
Thanks,
John

instead of switching between 2 topics, lets just stick to this thread.

I think the high side is used for evacuating the system, but I am not sure. You mention the pressure on the low side is 50psi. Is that during compressor cycling or when the compressor is off? If thats the pressure then the compressor is off, what pressure does it show when the compressor is running?

When the compressor runs, the gauge drops into the green, about 10 - 15 PSI. When the compressor stops running, it jumps into the yellow zone, 45 - 50 PSI.
John

That sounds almost normal. Might just need some more gas to bring it up to 20 or 25PSI. Once you do that, your compressor should stay on. Do you have the temperature set as low as it can go and the windows are down?

Yes. Temp is set to 60, & windows are down.
John

The proper way to charge a system is by using the high side pressure, car in the shade, windows up, large fan in front of the condenser. Then it is a function of the high side pressure, which is generally 2.2-2.5 times ambient temperature. Can't do a good diagnostic from the low side.

You can actually fill an AC system through the high side port??? I thought that was dangerous? I thought that was only for evacuating & venting.
I did have the car in the garage...plus, it was only 52 degrees outside.
John

You jumper on the connector.

Never fill on the high side. But DO read the pressure on the high side. That is the best measure of cooling capability.