Navien’s NPF Hydro-furnaces employ the same technology that’s behind the manufacturer’s tankless water heaters, combi-boilers, and boilers in an HVAC setting. Unlike traditional forced-air systems, the NPF Hydro-furnace heats water by burning the gas in a sealed stainless steel combustion heat exchanger isolated from the airstream. Heated water is then pumped through a hydronic heat exchanger that transfers the heat into the air. A variable-capacity blower and modulating combustion system allows the NPF to operate from 15% to 100% capacity for both natural gas and propane applications. navieninc.com
