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NFB‑C
NFB-399C certifications
NFB-399C
high efficiency Condensing Heating Boiler
  • 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
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Product Serial number is 15-16 digits and can be found either on the right side of the box or the back of the front cover.
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