The new Navien NFC series stainless steel fire tube combi-boilers will be available in two sizes, NFC-175 (175,000 BTU/H) and NFC-200 (199,900 BTU/H), each offering 95 percent AFUE, 11:1 turndown ratio, PVC venting up to 150 feet, high-altitude approval up to 10,100 feet, and industry leading residential and commercial warranties. The NFC models come with a patented in-house designed and manufactured heat exchanger, low profile burner for ease of service, advanced controls offering intuitive user navigation, a built-in DHW module, common venting capability up to 8 units, cascading capability up to 16 units, and built-in hardware to connect up to three zone pumps without a need for additional external controllers.
Navien also recently introduced the NFB-C commercial fire tube boiler. Shown in two sizes, NFB-C-301 (299,900 BTU/H) and NFB-C-399 (399,900 BTU/H), the NFB-C uses the same patented stainless steel fire tube technology from the NFB series released in 2018. The commercial fire tube boiler features 15:1 turndown ratio, 91.7 percent thermal efficiency, BACnet or LonWorks to BMS communication capability, and top and bottom water piping connections.