Our temps are hovering around the freezing mark now, our owb is our only source of heat so I keep it going as long as we need heat. It doesn't use a ton of wood in this weather, it is nice to have a deep coal bed when I go to reload. I feel one of the selling points of an owb is that you can burn wood in the mild weather and not be cooked out of the house. If the house doesn't call for much heat I still have the benefit of domestic water heating.