My A/C has been working pretty good, but I do have to have the fan on 3 on really hot days. A friend of mine has one of those recharge kits with the gauge on it, so I wanted to see how it worked. The guage has three areas with greenfor OK, blue for top off, and red for "Warning-something's wrong"!!!
Of course the gauge goes to the RED area. How accurate are those recharge kit gauges and should I worry about it even tho the A/C is working ok?

 

If it aint broke, don't **** with it.

R134 systems need to be accurately filled by weight.
Gauges only give you an indication of how the system is operating.
System pressures vary big time depending on temperature.
The low side of an R134 system operating with a cool engine compartment on a 70 degree day should be around 32 PSI. System pressures when A/C components are warm, engine compartment hot and outside air temp is hot will not give you an accurate indication of proper fill.

If you want to have the system serviced correctly, have a professional recover and recharge the system with the proper A/C equipment.

 

Thanks. I wanted to get confirmation from someone experienced.