Weil-McLain SlimFit SF750 702K 93.6% Hot Water Gas Boiler Direct Vent

Model: 383600331 Item Number: 79525
Weil-McLain 383600331
Weil-McLain 383600331
Weil-McLain 383600331
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Weil-McLain 383600331
Weil-McLain 383600331
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Our Price: $17,725.79
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$222 / Month
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Ships Thursday, July 25th
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Weil-McLain SlimFit SF750 702K 93.6% Hot Water Gas Boiler Direct Vent
Weil-McLain SlimFit SF750 702K 93.6% Hot Water Gas Boiler Direct Vent Model: 383600331 Item Number: 79525
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*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 map apply, see our full shipping policy for more details.
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*This product qualifies for Free Lift Gate Service. Items over 100lbs normally ship via semi-truck. Select this service if you need the product lowered to the ground curbside. To learn more about Lift Gate Service, read our shipping policy.
Specification Highlights
    New Learn More
    This product is new and has never been used. It's in its original packaging, which has not been opened.
    529 Pounds Learn More
    529 Pounds
    Total weight of the product and any included accessory/components. This total is not the shipping weight, as it does not include packing material, which may increase the overall shipping weight of this product.
    Product Category
Heating Capacity (BTU/Hr)
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Overview for Weil-McLain 383600331

Over the last 130 years, Weil-McLain has built the reputation of designing some of the most reliable boilers in the marketplace. Their dedication to producing long-lasting heating solutions is seen in every boiler they make. The SlimFit® is one of the most versatile, powerful, and efficient boilers on the market. Clocking in at 750,000 BTU with a thermal efficiency of 93.9%, the SF750 can bring excellent energy savings to the largest of commercial applications. Designed to be simple to install, maintain, and operate, the SlimFit® represents peace of mind in addition to comfort. Fully packaged and ready to install, the SlimFit's® durable components and easy-to-use controls round out what is one of the most impressive boilers in the marketplace. Ideal for every application from augmenting existing heating systems to headlining new construction, the SlimFit® is one of the best values in heating.
  • Industrial Power, Amazing Efficiency
  • The SlimFit® brings condensing technology and a modulating burner to industrial scale heating. These features bring efficiency gains in the form of reusing heat that escapes traditional boilers and scaling heat production precisely to your needs.
  • Cast-Aluminum Heat Exchanger
  • The Weil-McLain SF750 utilizes a cast-aluminum heat exchanger. The heat transfer properties of cast aluminum are superior to those of stainless steel; it heats faster and transfers that heat very efficiently.
  • Outdoor Reset Control
  • An outdoor reset sensor is included with every SlimFit® boiler. This sensor allows your boiler temperature to be adjusted relative to the temperature outside, eliminating excess energy use and guaranteeing comfort.
  • Installation Versatility
  • A low profile and two venting options mean that the SlimFit® can accommodate nearly any installation requirements. The SlimFit's® compact size can be the perfect solution for installations with difficult access to tight spaces.
  • Perfect for Retrofits
  • The SF750 is designed to be easily integrated with older, non-condensing boilers; a perfect way to increase efficiency by creating a hybrid system. It also comes fully factory-assembled for quick, on-site installation.
  • Advanced Boiler Controls
  • A user-friendly interface, full modulation for improved comfort and performance, warm weather shutdown, frost protection, and maintenance reminders are a few of many features that come standard on the SlimFit®.
  • Ultra Low NOx
  • The SlimFit® ;series helps keep peace of mind and harmful emmissions low by limiting NOx emission to less than 20 ppm.
  • Modbus® Connectivity
  • The SF750 features Modbus® connectivity, allowing for communication and control between up to 8 SlimFit® boilers and 24 circulators.
  • Product Includes:
  • (1) Weil-McLain SlimFit® SF750 Hot Water Boiler
  • (1) Outdoor Temperature Sensor
  • (1) Natural Gas to Propane Conversion Kit
  • Specifications
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    Product Category
    General Information
    Product Line
    Product Category
    Medium Learn More
    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
    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.
    Natural Gas
    Combustion Type Learn More
    Combustion Type
    Condensing appliances use leftover thermal energy from combustion gases to heat water in a secondary heat exchanger, resulting in higher efficiency and lower exhaust temperature.
    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.
    Direct Vent
    DHW Production Learn More
    DHW Production
    DHW (Domestic Hot Water) is potable water for uses other than space heat. Some boilers are able to provide DHW "out of the box", while others can do so with the purchase of optional accessories.
    Modulating/Staging Learn More
    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.
    Mount Type
    Includes Pump
    Assembly Type
    Gas Conversion Kit
    AFUE Learn More
    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.
    93 %
    Maximum Input Capacity Learn More
    Maximum Input Capacity
    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.
    750000 BTU
    Minimum Input Capacity
    150000 BTU
    DOE Heating Capacity Learn More
    DOE Heating Capacity
    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.
    702000 BTU
    Net I=B=R Capacity Learn More
    Net I=B=R Capacity
    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.
    610000 BTU
    Efficiency Type
    Thermal Efficiency
    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.
    Turndown Ratio
    Electrical Data
    120 Volts
    60 Hz
    Secondary Vent Pipe Diameter
    8 Inches
    Gas Connection Size
    1 1/4 Inches
    Flue Connection Size
    6 Inches
    Supply Connection
    2 Inches
    Return Connection
    2 Inches
    Product Height
    53 Inches
    Product Width
    47 1/4 Inches
    Product Depth
    18 3/16 Inches
    Product Weight
    529 Pounds
    Shipping Weight
    550 Pounds
    Country of Origin
    United States
    CSA Listed
    UL Listed
    ASME Certified
    AHRI Certified
    AHRI Reference Number
    Warranty Information
    Parts Warranty Show ACW Parts Warranty Learn More
    Parts Warranty
    A warranty is a safeguard from defects in manufacturing and can vary in length and terms. Some manufacturers require registration for extended warranty benefits, be sure to check out features and the warranty document. To see the manufacturer's warranty statement, click on the Manuals tab. Learn More
    2 Years
    Heat Exchanger Warranty
    10 Years
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    Weil-McLain SlimFit SF750 702K 93.6% Hot Water Gas Boiler Direct Vent
    Weil-McLain 383600331
    Weil-McLain 383600331
    Weil-McLain 383600331
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