Cast Iron Boilers

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Cast iron boilers are a popular choice for both hot water and steam heating applications. We carry a wide selection of cast iron boilers from the top brands, so you can be sure to find one for your needs.

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Brand

Weil-McLain (222)

Buderus (23)

Burnham (118)

Crown Boiler Co. (140)

Peerless (7)

Williamson-Thermoflo (4)

Net I=B=R Capacity (BTU)

I=B=R, also referred to as Net Output or AHRI Capacity, is the rated heat output of a boiler after accounting for combustion efficiency, piping loss, and an extra pickup factor. We recommend sizing steam boilers based on the I=B=R rating.

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1980000+ (1)

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DOE Heating Capacity (BTU)

Also referred to as Gross Output, this is the output of a boiler after accounting for combustion efficiency. We recommend sizing hot water boilers based on the DOE Heating Capacity.

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Maximum Input Capacity (BTU)

The Maximum Input Capacity describes how quickly the appliance will use fuel when delivering it's maximum capacity. The units may change depending on the fuel being used.

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2830000+ (2)

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AFUE (%)

AFUE (Annual Fuel Utilization Efficiency) measures the efficiency of combustion equipment over the entire heating season, and is calculated by dividing the amount of energy that is actually heating your home by the total energy contained in the fuel used by the boiler/furnace. Learn More

81 (46)

82 (89)

83 (52)

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87 (15)

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Efficiency (%)

77 (3)

82 (3)

Vent Type

Products that use combustion (burning) of fuel to create heat also create potentially dangerous gasses that need to be exhausted (AKA "Vented"). Depending on the product, venting can be done via a chimney, through a side wall, or use a second vent to provide fresh air to the appliance.

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Power Vent (64)

Medium

Medium refers to the substance that carries heat through the heating system. Systems are either designed to use either Hot Water or Steam as a medium, and components are usually specific to one or the other.

Hot Water (370)

Steam (144)

Fuel Type

To create heat, some form of fuel is required. Fuel Type specifies what the product uses as an input to create heat.

Liquid Propane (120)

Natural Gas (288)

Oil (100)

Oil/Natural Gas (6)

Weil-McLain CGa-4-PIDN - 88K BTU - 84.0% AFUE - Hot Water Gas Boiler - Chimney Vent

Model: 381357804

Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 105K BTU Gross Input, 88K BTU DOE Capacity, 77K BTU Net IBR Capacity. Includes Circulator.

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$1,935.00

In-Stock

Free Shipping & Lift Gate

*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges may apply, see our full shipping policy for more details.

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Save 2% instantly by using our convenient "e-check" option or by simply mailing us a paper check. Yes, your order will be delayed slightly (5 business days). But, if you can wait, the savings are significant.