Crown Boiler’s Phantom stainless-steel condensing boiler fires at AFUEs up to 94% and features a water-tube heat exchanger. It is offered in five sizes — 80, 100, 120 150 and 180 MBH — with four more sizes (210, 285, 399 and 500 MBH. It features a compact design for wall-mount installation; a touchscreen user interface; a modulating burner with a 5:1 turndown ratio; and an intelligent boiler control. The standard outdoor reset function allows the boiler to adapt proportionately to outdoor temperature changes.