Description

Note: product title indicates boiler’s Net AHRI (Net IBR) rating.
Williamson GWI series boiler is a fan-assisted (Power Vent) type cast iron hot water gas boiler designed for new and replacement installations where conventional chimney venting is not available or impractical. It’s a cost-attractive and high-quality unit with streamlined design and industry-leading, familiar controls (concealed behind easy-access front panel).
Boiler includes: Fasco draft inducer fan, Taco 007 circulator & flanges, Resideo gas valve, Hydrolevel 1100H8 LWCO, Williamson 1135-611 gas control, Hartland transformer (model 571842371), pressure relief valve, tridicator gauge, drain valve and other components shown in the photos.

Features:

Manufactured in the USA
Factory-packaged and assembled
Power vent design for side wall venting
Premium-level, familiar controls/components include Honeywell/Resideo Gas Valve, Taco 007 circulator, Hydrolevel 1100H8 LWCO, Williamson 1135-611 Gas Control, Fasco Draft Inducer and Hartland Transformer
Cast iron sections w/ built-in air separator
One-piece front access door for easy service
Insulated heavy-gauge jacket
Left-side piping
Approved for up to 2,000ft altitude installations (derates 4% for every additional 1,000ft – no kit needed)
CSA certified for installation on combustible flooring (but not carpets)

Technical Specifications:

Input (BTU): 90,000
Net AHRI Rating (BTU): 66,000
DOE Heating Capacity (BTU): 77,000
Efficiency (AFUE): 84.0%
Fuel Type: Natural Gas
Boiler/System Type: Hot Water (Hydronic) Cast Iron Gas Boiler
Boiler Connections: 1-1/4″ Supply/Return Connections (recommended pipe size is 1″), 3/4″ NPT – Relief Valve, 3/4″ NPT – Drain, 1/2″ NPT – Gas
Pressure Specs: 30 psi relief valve setting, 50 psi max. allowed working pressure
Internal Water Volume (Gal): 2.1
Vent Type: Power Vent (using indoor air for combustion)
Vent Pipe Size: 3″ (Cat III, AL29-4C vent pipe – any brand)
Electrical: 120V, 1-phase, 60Hz
Dimensions: 13″ Wide (22″ incl. inducer fan) x 23″ Deep x 29″ High
Weight: 230 lbs (approx. ship weight)