Furnace Size Calculator
Calculate furnace heating capacity for home size and climate.
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What This Calculator Does
Calculate furnace heating capacity for home size and climate.
It combines Home Square Footage, Climate Zone, Insulation Quality, Furnace Efficiency to estimate Recommended Furnace Size, Heating Load, Furnace Input Rating.
Formula & Method
Notation used in the formulas: R = Recommended Furnace Size; x_{1} = Home Square Footage; x_{2} = Climate Zone; x_{3} = Insulation Quality; x_{4} = Furnace Efficiency; x_{5} = Ceiling Height.
Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.
Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.
Inputs Used
- Home Square Footage: Used directly in the calculation.
- Climate Zone: Used directly in the calculation.
- Insulation Quality: Used directly in the calculation.
- Furnace Efficiency: AFUE rating
- Ceiling Height: Used directly in the calculation.
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