99 silverado ac drier frosts up

[ngooch2]

99 silverado 5.3
Replaced compressor, drier, orifice, manifold line, condensor, flushed evaporator, pulled vacuum for couple hrs, let it sit, no leaks, installed about 2 1/2 to 3 cans of r134, cools great but after a couple of minutes the drier frosts over, any help would be appreciated

[Tim]

Which thread do you want to use? Having 2 of the same post is not the best for responses.

[Dougflas]

Please give more info as rpm (should be 1500) Max cool. doors/windows open, low side psi, high side psi, Ambient temp, humidity, vent temps, does compressor clutch stay engaged?

[JohnHere]

According to my references, the Crew Cab model takes 36 ounces of R-134a while the regular cab model takes 32 ounces. Charged directly from the small "12-ounce" cans without using the proper equipment, you won't notice that the actual amount each can holds often varies quite a bit. So I think what we have here is an incorrect charge amount.

[GM Tech]

Frosty A/D is Bad? News to me. Really humid conditions shows great cooling....