I've never heard that a Garn leaks steam everywhere, at least no more than any other open system. Now there are some pros and cons to an open system, the cost of water treatment and ongoing water testing being a con to an open system. Closed (pressurized) systems probably will have a longer life, I just don't know of any that are packaged in an outdoor boiler type package. I saw enough cons to an open system that both my shop and house systems are closed systems.Reading articles on this forum and others you get many conflicting opinions about products, warranties and Customer service. I do not see many articles ore reviews about Polar furnaces. I compared their warranty and product specs to the cleanfire and the cleanfire came out ahead. I will keep searching for info on both units or if another option comes up. I am looking for 170-200+Kbtu's, 250+ gallons of water storage, and indoor installation. The Garn looked interesting but it is an open system that pisses steam everywhere, this unit will be installed close to some neighbors. The search continues!