I went to EPCOT yesterday and rode Spaceship Earth, Living with the Land and watched American Adventure. It was uncommonly cool and very nice outside yesterday for this time of year, in the 70's and getting even cooler by nighttime. Yet all three attractions were very hot inside (far hotter than the outside). SSE probably being the worst. The Land's problems are probably partially related to the busted doors to the greenhouse scenes, which are now perpetually kept in an open position (so improperly climate controlled air is travelling inside the rest of the showscenes). I have no doubt that the improper climate control results in the opposite problem when the weather drops into the 40's during the short winter season (causing rides to get colder than they should at those times). Though the majority of the year in Florida is extremely hot (90's and 100's mostly), so the lack of air conditioning is more glaring than a lack of heat. Either way, the climate control is very poor in most areas at WDW these days, and these issues were actually discussed on these forums a few years ago and confirmed by people with connections inside the company. One of the few places I still feel has good climate control is inside one of the buildings for Innoventions (an empty corridor near a character meet n greet that has a timeline of EPCOT's attraction history on the wall).
The monorails and even boat transport are also sweltering in the hotter months for the past few years. And all the times i've ridden Little Mermaid at MK the air conditioning has been extremely poor (there's even a place where additional cool air is supposed to blast you as you go below the "water surface", an effect that doesn't work when the air is not cool).
