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Preferred™ Series BW3 Boiler

Radiant Heat Versatility for Reliable Home Comfort

Our most versatile gas-fired, radiant heat system, engineered with an up to 84.4% AFUE rating for outstanding energy efficiency. Rugged cast-iron construction and compact design make it a value-add fit for any home.

AFUE Efficiency :
Up to 84.4%
  • Up to 84.4% AFUE
  • Cast iron heat exchanger
  • Gas-fired models
  • Stainless steel/titanium alloy composite burners
  • Fiberglass insulated casing
  • Small, compact design
  • 5-year parts limited warranty and a 20-year parts limited warranty on heat exchanger section1

1 To the original owner, the Bryant BW boiler is covered by a 5-year parts limited warranty and a 20-year parts limited warranty on the heat exchanger section. Ask your Bryant dealer about optional extended warranties, which may include labor. See warranty certificate at for complete details.


Energy Efficiency Up to 84.4% AFUE                               
Rated Heating Input 42,500 - 187,000 BTUH
Rated Heating Capacity 36,000 -158,000 BTUH
Heat Format Water


Control Type Integrated boiler control


Heat Exchanger Cast iron
Burners Titanium composite
Ignition Intermittent pilot
Vent damper Induced-draft
Fuel Gas


Casing Full fiberglass insulation
Section Seals Cast iron push nipples
Bryant reserves the right to discontinue or change any specification or design without prior notice or obligation.

California residents please see Proposition 65