i refill my sister a/c system with r134a with the one from the auto part store and it still wasn't cool.. i couldn't figure it out, so i ask her to take into an AC shop call With Pride and the AC guy say that it was okay and the AC valve just need to be adjusted.. after he did that the ac system work great and he didn't charge her for adjusting it. i wasn't there so i didn't know were the ac valve is located at.. hopefully someone on here knows were it's located at.