and how did he check this? If he says gas is converted to air, im sure his 7th sense told him it was full.
I went through the same bullshit logic given by all dealerships. In the end the gas was less, because 1 o-ring on the condenser had hardened that caused it to leak over time. I changed all the o-rings, refilled appropriate compressor oil, 4th summer now, perfect cooling.