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Heat Loss
at design based on annual fuel consumption

Annual heat fuel use can be estimated based on your location, the design heat load, and your fuel use. Select the fuel you use, the AFUE of your heating system, and the annual units of fuel you use for heating. We will use the Manual J Degree Days and 97.5% Outdoor Design Temperature based on your current location. Output is the minimum BtuH output heating device that you need to maintain design conditions in your space.



*Seasonal Heating Degree Days and Design temperature Δ°F is based on Burlington VT

**C-factor reflects seasonal heat gains to the home combined with thermal storage by the building materials. These gains come in multiple forms, including solar gains, as well as internal gains from such sources as lighting, appliance heat, and occupants.