Any way to tell a/c system?

[rpastir]

Hi All,

Is there any way to tell if the a/c system has been upgraded to 134a just by looking at the a/c components?

Thanks-
Rob

[DaddyGlenn]

If I remember correctly, the fill valves are larger in diameter.

[Jim Sims]

A "correctly done" conversion will have label stating it was done and the oil type used in the conversion. Take a plastic cap (red, blue or black colored) off one of the servicing fittings; if the form of the outside of the fitting looks something like the below image (metal color doesn't matter) it has been converted.