Hello, I have a question. We've been here for six months and the room …

Hello, I have a question. We've been here for six months and the room where the child spends most of their time is very stuffy. The window and door are always open but it doesn't make any difference, it's unbearably hot. The child sweats profusely even though they're only wearing a onesie and diaper. Can we turn on the air conditioner? I'm afraid he might get sick, but it's also harmful to be so hot. The child has started writing less and trying to drink water but he doesn't want to drink...?