Five models with heating inputs of 42,500 to 187,500 Btuh • AFUE - Up to 84.4% • Natural gas or LPG/Propane (LPG with optional conversion kit) • Boiler applications include radiant floor heating, baseboard heating and zoned heating systems • Compact size allows easy installation in a basement or utility room • Shipped factory assembled with all controls installed and wired • Each unit is factory test operated to ensure dependable performance