Heating Method Steam AHRI Net BtuH 107 000 BtuH Heating Capacity Input 172 000 BtuH Heating Capacity Output 142 000 BtuH Annual Fuel Utilization Efficiency 82.1 Percent Boiler Type Atmospheric Vent Steam Boiler Vent Diameter 6 in Return Connection Size 2 in Free Air CFM @ 10 Vacuum 2 in Series Bermuda Overall Height 40 7/16 in Overall Width 22 1/2 in Overall Depth 28 in Compatible with Product Type Home Heating Systems Manufacturers Warranty Length 1 yr Limited