We are getting ready to do a major overhaul to about half of our house. We currently heat with an old wood furnace tied to an oil furnace setup. The house originally had no insulation and this setup struggled to keep the house at 65 on cold days here in Maine. We burned cloe to a cord or wood a week when it was really cold.
I air sealed and insulated the attic to R50 and insulated the rim joist and top 4' of the basement a couple of years ago. Now it is a challenge to keep the fire low enough to not over heat the house. The walls are still empty.
The house is a 1400 ft2 ranch. I plan to gut about half of it this spring. I will be replacing the windows with something decent, but not top of the line. I plan to put 3" (R20) of closed cell spray foam in the walls and then 1" of rigid foam on the inside to minimize thermal bridging. There is currently a fireplace with an insert in the living room which I plan to remove. Also I can shut off 2 rooms at the end of the house during real cold weather to reduce the area to 1100 ft2.
Now to my actual question. I plan heat the house with a single direct vent propane heater. I haven't done any load calcs yet, but probably need a unit that produces around 40000 btu/hr. Does anyone have any suggestions as to what model to install?
There will also be a small wood stove in the basement for supplemental heat when necessary.