Navien Combi Boilers

A Navien combi boiler heats the home and makes domestic hot water on demand from one wall-hung condensing appliance, so there is no separate water heater or indirect tank. We stock two series. The NCB-H (NCB-240/110H and NCB-240/130H) pairs 110,000 or 130,000 BTU/h of heating input with 199,900 BTU/h for hot water. The larger NFC-H (NFC-250/175H and NFC-250/200H) offers 175,000 or 199,900 BTU/h of heating with 210,000 BTU/h for hot water.

How to choose a Navien combi

Size it by two numbers. The heating input should cover the building's calculated heat loss, and the hot water side has to keep up with the fixtures that run at the same time. A combi that heats the house well can still be short for two showers at once, so check the hot water flow at your temperature rise. Plan for PVC, CPVC or polypropylene venting, a condensate drain with a neutralizer, and a gas line sized for the full input.

Compare every model side by side in the Navien model comparison. See also all Navien boilers, including heating-only NHB and NFB models, combi boilers from other brands, condensate neutralizers and Navien parts and vent kits.