The KC-1M cast iron, direct-vent boiler from HydroTherm packs up to one million Btus in a compact footprint, with efficiency up to 91%. Features include a three-to-one turndown, condensing design, precision-machined cast iron sections with graphite port connections and a corrosion-resistant ceramic burner. Its low noise boiler and low velocity burner make for quiet operation with low CO and NOx emission. The compact KC-1M fits through a standard doorway for easy installation, and the direct-vent capability provides flexibility. The down fire design simplifies burner service, and all critical components are easily accessible. HydroTherm.