I would try to work through the problem. When the daughter sleeps on the floor with a space heater there's sure to be problems. If he can't find her a decent place to sleep keep her at home. The courts would be on your side. A child should not have to sleep on the floor.
Talk to her dad. Even if you both don't get along, you have a daughter to take care of. its best to figure out whats going on and if that doesn't work take it to court, your daughter needs a warm bed to sleep in.
I would recommend keep sending her if it is court ordered. If not you don't have to.But if it also court ordered you can go to the court and have your daughter tell them what she has told you Best advice can give you