I have a 3.5 ton Arcoaire A/C that is about 20 years old. It isn't cooling, the suction valve is frosted so I tried to add F22. For some reason it will not take a charge. Then, when I check my gauges I find the suction pressure higher than the High Side pressure. What am I doing wrong?

Maynard

A. You are doing something that you have no clue about.
It is time to take lessons at a vocational school.

http://www.refrigtech.com/charge.html

www.heatpro.us energy businessmen's knowledge

Yes, you really have to find out the MAKE and MODEL to get good answers. There IS more than one machine made.