Lochinvar’s FTXL fire tube boiler is designed with a stainless-steel fire tube heat exchanger. It delivers 98% thermal efficiency and 10:1 turndown. The line includes five models with inputs ranging from 399,000 Btu/hr. to 850,000 Btu/hr. With a built-in cascading sequencer, up to eight FTXL units can operate efficiently with total inputs of up to 6.8 million Btu/hr. Each model features the same compact size with a 6.2-sq.-ft. footprint. The operating system allows for remote communication with the boiler via Wi-Fi or a wired Internet connection.