Boilers

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Fuel Type Learn More
Fuel Type
To create heat, some form of fuel is required. Fuel Type specifies what the product uses as an input to create heat.
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DOE Heating Capacity (BTU) Learn More
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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Net I=B=R Capacity (BTU) Learn More
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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Maximum Input Capacity (BTU) Learn More
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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AFUE (%) Learn More
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.
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Vent Type Learn More
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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Medium Learn More
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.
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Modulating/Staging Learn More
Modulating/Staging
Stages are unique speeds or levels that equipment can operate at. More stages allow for better fine-tuned control of output, which improves comfort and efficiency. Modulating equipment can operate across a range of levels, giving the highest level of fine-tuned control.
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Efficiency (%)
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Installation Location
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Low NOx Emissions Learn More
Low NOx Emissions
NOx is a byproduct of the combustion process, and it's output is regulated in some jurisdictions. Many regulators mirror SCAQMD rules, which regulate air quality for some parts of Southern California. Low NOx appliances emit less than 40 ng/J (nanogram per Joule) of NOx.
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Ultra Low NOx Emissions Learn More
Ultra Low NOx Emissions
NOx is a byproduct of the combustion process, and it's output is regulated in some jurisdictions. Many regulators mirror SCAQMD rules, which regulate air quality for some parts of Southern California. Ultra Low NOx appliances emit less than 10-14 ng/J (nanogram per Joule) of NOx.
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Floor Mounted, Condensing Boiler with Modulating Gas Valve. Ships Packaged. Ratings: 2,000K BTU Gross Input, 1,920K BTU DOE Capacity, 1,670K Net IBR Capacity
Item#: 102997
Model#: 384000024
Brand: Weil-McLain
$44,219.00
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Floor Mounted, Condensing Boiler with Modulating Gas Valve. Ships Packaged. Ratings: 3,000K BTU Gross Input, 2,880K BTU DOE Capacity, 2,504K Net IBR Capacity
Item#: 102998
Model#: 384000027
Brand: Weil-McLain
$62,776.00
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Floor Mounted, Condensing Boiler with Modulating Gas Valve. Ships Packaged. Ratings: 2,500K BTU Gross Input, 2,400K BTU DOE Capacity, 2,087K Net IBR Capacity
Item#: 102999
Model#: 384000028
Brand: Weil-McLain
$55,395.00
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Wall Mounted, Condensing Combi Boiler with Modulating Gas Valve. Ships Packaged. Ratings: 180K BTU Gross Input, 169K BTU DOE Capacity, 147K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103078
Brand: Crown Boiler Co.
Sale: $1,780.00
On Sale Through 06/24
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Wall Mounted, Condensing Boiler with Modulating Gas Valve. Ships Packaged. Ratings: 85K BTU Gross Input, 79K BTU DOE Capacity, 69K BTU Net IBR Capacity.
Item#: 103081
Brand: Crown Boiler Co.
$3,709.00
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Wall Mounted, Condensing Boiler with Modulating Gas Valve. Ships Packaged. Ratings: 110K BTU Gross Input, 103K BTU DOE Capacity, 90K BTU Net IBR Capacity.
Item#: 103082
Brand: Crown Boiler Co.
$3,915.00
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Wall Mounted, Condensing Boiler with Modulating Gas Valve. Ships Packaged. Ratings: 205K BTU Gross Input, 189K BTU DOE Capacity, 164K BTU Net IBR Capacity.
Item#: 103084
Brand: Crown Boiler Co.
$5,614.00
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Wall Mounted, Condensing Boiler with Modulating Gas Valve. Ships Packaged. Ratings: 270K BTU Gross Input, 252K BTU DOE Capacity, 219K BTU Net IBR Capacity.
Item#: 103085
Brand: Crown Boiler Co.
$6,644.00
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Wall Mounted, Condensing Boiler with Modulating Gas Valve. Ships Packaged. Ratings: 320K BTU Gross Input, 304K BTU DOE Capacity, 264K BTU Net IBR Capacity.
Item#: 103086
Brand: Crown Boiler Co.
$8,500.00
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Wall Mounted, Condensing Boiler with Modulating Gas Valve. Ships Packaged. Ratings: 399K BTU Gross Input, 379K BTU DOE Capacity, 330K BTU Net IBR Capacity.
Item#: 103087
Brand: Crown Boiler Co.
$10,900.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 38K BTU Gross Input, 32K BTU DOE Capacity, 28K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103088
Brand: Crown Boiler Co.
$2,231.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 38K BTU Gross Input, 32K BTU DOE Capacity, 28K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103089
Brand: Crown Boiler Co.
$2,200.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 70K BTU Gross Input, 59K BTU DOE Capacity, 51K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103090
Brand: Crown Boiler Co.
$2,421.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 70K BTU Gross Input, 59K BTU DOE Capacity, 51K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103091
Brand: Crown Boiler Co.
$2,421.00
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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 Taco Circulator.
Item#: 103093
Brand: Crown Boiler Co.
$2,584.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 140K BTU Gross Input, 117K BTU DOE Capacity, 102K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103094
Brand: Crown Boiler Co.
$2,821.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 175K BTU Gross Input, 146K BTU DOE Capacity, 127K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103096
Brand: Crown Boiler Co.
$3,175.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 175K BTU Gross Input, 146K BTU DOE Capacity, 127K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103097
Brand: Crown Boiler Co.
$3,109.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 210K BTU Gross Input, 176K BTU DOE Capacity, 153K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103098
Brand: Crown Boiler Co.
$3,569.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 210K BTU Gross Input, 176K BTU DOE Capacity, 153K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103099
Brand: Crown Boiler Co.
$3,569.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 280K BTU Gross Input, 234K BTU DOE Capacity, 203K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103102
Brand: Crown Boiler Co.
$4,219.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 70K BTU Gross Input, 59K BTU DOE Capacity, 51K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103104
Brand: Crown Boiler Co.
$2,421.00
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Floor Mounted, Cast Iron Boiler with Single Stage Gas Valve. Ships Packaged. Ratings: 70K BTU Gross Input, 59K BTU DOE Capacity, 51K BTU Net IBR Capacity. Includes Taco Circulator.
Item#: 103105
Brand: Crown Boiler Co.
$2,421.00
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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 Taco Circulator.
Item#: 103106
Brand: Crown Boiler Co.
$2,584.00
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Tools & Articles
How to Pick a Residential Boiler
Home Boiler System Overview

Boilers at ACWholesalers

A boiler is a central heating system that uses hot water or steam, which is transported through a piping system and to radiators, to heat a home.

One advantage of choosing a residential boiler system is the even distribution of heat. Hot water and steam transfer heat more effectively than air by keeping the heat closer to the ground. Another advantage is efficiency. Boilers require less energy to heat a home than forced-air systems because hot water and steam hold heat longer than air.

Residential boilers also provide flexibility by allowing for zoning different areas of the home. This way, each zone can be kept at its own temperature, maximizing comfort and reducing energy costs for areas where additional heat isn't needed.

Choosing a Residential Boiler System

Medium

A boiler can transfer heat using hot water or steam as its medium. These mediums are not interchangeable, so it is important to know what the existing pipe system is designed for.

Fuel Type

A residential boiler system is made to use one of the following as its fuel source: natural gas, liquid propane, oil, or electricity.

Vent Type

There are three venting options for a residential boiler; direct vent, chimney vent, and power vent. Each type has a different method of removing gasses and is chosen based on the home's construction and desired efficiency of the new system.

Net I=B=R Capacity (BTU) or DOE Heating Capacity (BTU)

Steam boilers are often sized based on their Net I=B=R capacity. This BTU amount factors in piping loss, combustion efficiency, and an extra pickup factor. DOE (Department of Energy) heating capacity also factors in combustion efficiency and is commonly used to size hot water boilers.

AFUE (%)

A boiler's AFUE (Annual Fuel Utilization Efficiency) percentage describes its efficiency. The higher the percentage, the less energy is wasted and the more efficient the model is.