You don’t have any cats and the place is warm with no drafts, so unless there is something that he could nibble or land on that would make him sick, he’d be okay.
[Obviously ceiling fans or all fans should be off if they aren’t already.]
All fans are cage-protected. Nothing he could land on and hurt himself. I worry about the curtains and the little feeties getting caught, but I think he will be fine if I open the door to his cage...