^^ Not exactly - thats what the thermostatic expansion valve is for, it controls flow of gas to keep the evaporator chilled.
Anyways Ive seen people talking about door insulation n stuff. If you look at a new cars doors they are sealed off with plastic on the inside - that serves two purposes
1 seal the interior from moisture (rain, wash from the windows)
2 seal the interior from hot air seeping in through the door cards air is a good insulator and the hot air then exhausts from the door drains or window channel seals outside
I always install this plastic whenever I see it missing or diminished (its the same stuff you can buy at book stores) and I seal it with black silicone - always worked for me in every car which had poor a/c performance, fogged up windows in rain etc