Outdoor wood furnace capable of heating up to 5,000 square feet. This furnace features shaker grates and ash pan for easy ash removal, stainless steel construction for better corrosion resistance and tolerance to expansion and contraction. It also features an easy to see water level indicator for ease of operations. It also has a round firebox so that the wood doesn't bridge up and not burn. It is a non pressurized system making blowups virtually impossible. Call Phil or email us. For a complete list of available models paste http://www.heatmasterwoodboilers.webs.com in your browser. Also check HeatmasterSS out on YouTube.