i have the Jotul 550 for three years and can get the house up to temp easily. What I don't know is how to just not overheat or let the fire go out. I have been getting a good fire in the aM then only adding two small at a time through the day. It works but not sure how economical my method is? BTW my unit is in a huge central stone faced masonry central fire place a good 6X3 feet around and 12 ft tall.