Water Heater, Tankless, Liquid Propane, Input (BTU) 225, 000, 4.6 GPM @ 90F Rise, 9.2 GPM @ 45F Rise, Gas Connection (In.) 3/4, Ignition Type Electronic, Standards CSA, Manufacturers Warranty Length 2 Year Limited Warranty on Heat Exchanger, 5 Year Limited Warranty on All Other Parts, Tankless, Water Heater, Includes Wall Mounting Bracket, Pressure Relief Valve Bosch Gas Tankless Water Heaters1LXD1 and 1LXD2 require no battery or external power source. No standing pilot light. 2KJG9 and 2KJH1 have direct-vent, room-sealed combustion operation. No standing pilot light. Greater than 83% thermal efficiency. Energy Star qualified. Condensing models include modulating feature for higher efficiency; up to 98% thermal efficiency. ASME certified; meet CSA standards. 6FZP2 and 6FZP3 are for residential use. 6FZP4 and 6FZW5 are for commercial use (100 to 180 F). Up to 94% thermal efficiency. Intelligent cascading for up to 24 units. 5-yr. limited manufacturer's warranty on heat exchanger and parts. Horizontal Vent Kit 2KLG1 has a max. temp. of 500 F.