A/C Questions

[TwistedD85]

I was checking the pressure in the A/C this morning and while it was running on Max A/C the pressure gradually rose from 15 to 50, clicked, dropped, then started all over again. Normally I'd say I need refrigerant, but apparently 50 is in the warning zone on the gauge, is it normal for it to cycle to nearly 50psi when it's low on refrigerant? I just want to make sure I'm reading things right is all, that and if I should add any, when I added it last it only cycled from around 15 to maybe 25 at best so I'm concerned about adding any additional freon until I'm sure. :thankyou:

 

[projectSHO89]

The pressure cycling witch is designed to open around 45 psi ascending and to close at around 22 psi descending. That's why it's called a "cycling" switch.

You cannot accurately diagnose an AC system with a low-side only reading. It would be like trying to watch a 3-D movie with one eye closed.

System pressures will vary with the load on the system. Charts for pressure and cycle times ALWAYS assume that you followed the prerequisites specified by the manufacturer and that you have compensated for ambient temperature and humidity.

 

[TwistedD85]

Ah, alright. Gotta see if I can get a set of gauges that won't break the bank, A/C shops around here are real crooks, can't trust 'em.