Question: I am interested in purchasing the largest woodstove with the most heat BTU output which will fit into my fireplace opening. I am somewhat confused as to which stove to buy after looking at the factory BTU ratings and the Lehmans BTU chart. I see some of the stoves are rated to put out 55,000-80,000 and Lehmans chart cuts some of them down almost in half! The 1 stove I was looking to buy is only rated for 37,000 BTU output-I have a 35,000 BTU furnace in my travel trailer. Any thoughts on this comparison table? Thanks Answer: Perhaps Lehmans is being realistic as to the everyday output of these models, instead of the factory rated maximum. 30,000+ BTU is a lot of heat. For instance, where I live (mid-atlantic area), 35,000 BTU per hour would heat a 1500 sq foot well insulated cape cod house in virtually any weather. Another factor to use when comparing similar stoves is the firebox size. A larger firebox usually = more heat and longer burns.