@Maryann41 Not sure why you would allow a 4 week booking from someone whose habits you weren't aware of and without conveying anything about your expectations of how much the guest would be around. Vacationers are often out and about, long term guests usually are not, and you have to find out ahead of time if a guest's lifestyle jives with yours if you are going to take long term bookings in a home-share.
Of course you have to leave the heating on when you have a guest in residence.
You can shorten the booking if you don't want this guy there anymore. That's pretty much your only choice. Or talk to him about a kitchen schedule and whatever is irritating you, but as there was no discussion about hanging around the house all the time, he can't be told he can't.