bsi138Buy Crown Boiler Co. BSI138ENPZZPSU Free Shipping. Check the Crown Boiler Bermuda - 85K BTU - 82.0% AFUE - Steam Gas Boiler - Chimney Vent ratings beforeBermuda Gas Fired Cast Iron Steam Boiler BSI series, Sea Level. BtuH Input: 138,000; Gas Type: NG; Sections: 5; AFUE: 82.0%; Flue Diam.: 6; Width: 19-14; Heht