Navien has made available its next generation combi boiler, the NCB-E. Navien’s NCB series, as one unit, is capable of providing a wholehouse heating system while providing the domestic hot-water output of a stand-alone tankless water heater. The NCB-E will be a rolling replacement, now with a Grundfos pump, an integral air vent, a PRV top connection, quieter fan and new front cover bevel design.