The Triple-Flex Ultra-High Efficiency Condensing “Flexible Water Tube” Boilers (photo) offer a guaranteed minimum thermal efficiency of 90% in worst-case condensing boiler operating conditions (such as 160°F return water and 180°F supply water at 100% firing load). Efficiencies of 99% are achievable with lower return-water temperatures. The Triple-Flex boilers fire at 3,000,000 Btu input, with less than 30 ppm NOx levels, utilizing a hybrid metal fiber 5:1 turndown burner, and Honeywell SOLA hydronic safety controls and interface systems. Other features include easily replaceable stainless-steel flexible tubes, a variable speed combustion air blower and easy-to-remove access panels that make the boiler interior accessible for both service and inspection. — Bryan Steam LLC, Peru, IN