NFB-399C

Categories: Navien, Boilers

97.5% TE Industry Leading Thermal Efficiency
Patented stainless steel fire tube heat exchanger
160 PSI maximum operating pressure
Advanced controls with intuitive 7” color display
Up to 15:1 TDR (turndown ratio)
BAS communication capability
Common vent up to 4 and cascade up to 32 units
Top & bottom piping

NFB-399C premium features and benefits

Multiple venting options. Low exhaust gas temperatures allow use of PVC, CPVC, polypropylene (rigid and flexible) and stainless-steel venting reducing installation time and costs.

Patented stainless steel fire tube heat exchangerNavien’s innovative heat exchanger design is ASME‑Certified,“H” Stamped, and reduces high-stress point weld failures common on other combi-boilers.

Dual Venturi and field gas convertibility. Dual Venturi system creates better combustion control and turndown ratio. Orifice for easy field gas convertibility from NG to LP. Conversion kits included.

Top and bottom piping
Easy pipe connections for floor or wall-hung installations.

Low gas pressure operation. Negative pressure regulating gas valve ensures maximum performance all the way down to 3.5″ of water column on natural gas and 8″ of water column on propane gas.

Built-in hardware connects boiler pump & 3 zone pumps. All integrated into the NFB-C circuit board. Also includes a DHW priority zone

Advanced 7″ touch screen controls Easy intuitive navigation for setup, troubleshooting and operation.Built-in USB port
Download boiler data and settings. Upload software updates and boiler settings.

Specifications

Item		NFB-399C
Water volume		36.3 l (9.6 gal)
Dimensions		63.8cm W x 83.3cm H x 56.6cm D (25.1″ W x 32.8″ H x 22.3″ D)
Boiler weight		126.1 kg (278 lbs)
Boiler Weight With Water		168.3 kg (371 lbs)
Installation type		Indoor wall-hung
Venting type		Forced draft direct vent and non-direct vent (single pipe)`
Ignition		Electronic ignition
Natural gas supply pressure (from source)		3.5 ” WC to 10.5 ” WC
Propane gas supply pressure (from source)		8 ” WC to 13.5 ” WC
Natural gas manifold pressure (min-max)		-0.03 ” WC to -1.9 ” WC
Propane gas manifold pressure (min-max)		-0.01 ” WC to -0.9 ” WC
Connection sizes	Gas inlet	3/4″ NPT
Power supply	Main supply	120V AC, 60Hz
Power supply	Maximum power consumption	Less than 12 amperes
Materials	Casing	Cold rolled carbon steel
Materials	Heat exchangers	Stainless steel
Venting	Exhaust	3″ or 4″ PVC, CPVC, PP and SS / 3″ or 4″ special gas vent type BH (Class III, A/B/C
	Intake	3″ or 4″ PVC, CPVC, PP and SS / 3″ or 4″ special gas vent type BH, (Class III, A/B/C)
	Vent clearances	0″ to combustibles
Safety Devices		Flame rod, APS, Ignition operation detector, Water temperature high limit switch, Exhaust temperature high limit sensor, Water pressure sensor