I have had this stove for 3 years. Bought it used. I’ve never had a owb before, so really don’t know what to expect as far as efficiency. I load a wheel barrel into my boiler 3-4 times a day to heat a 4500 sf home with both in floor heat and a furnace with an A coil. All I know is that I havnt used any LP to heat my house since I got it, and I have 40 acres of all trees to feed the boiler. If I could find a manual, I could prolly set it up to be more efficient, but I guess I don’t know what I don’t know. Any advice would be appreciated. A new boiler is prolly not in my budget right now, even though the setup you have sounds NICE! Maybe next year!