The 1537G Hotblast Furnace works alone or in conjunction with your existing furnace to heat your entire home, while drastically reducing home heating costs. Twin 550-CFM blowers, Automatic bi-metallic thermostat, extra heavy duty cast-iron grates and liners. Heat output is 119,000 BTU's hr. The Capacity is 2,500 square ft. This unit has a 6" flue collar size with (2) 8" Heat outlets. The Dimensions are 40" H x 24" W x 40" L. Firebox Construction of single front - Full 7 gauge with Firebrick Lining. Clearance to Combustibles: Sides- 12"; Front- 48"; Back- 30". The weight is 500 lbs. Wood or Coal burning furnace.