BTU Heating Calculator — Furnace & Boiler Sizing
How does climate zone affect heating load?
Climate zone sets the design outdoor temperature — the colder the zone, the larger the temperature difference between indoors and outdoors, which increases conductive and infiltration losses. The same 2,000 sq ft house needs about 40% more heating capacity in zone 7 than in zone 4.
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Use the BTU Heating Calculator — Furnace & Boiler Sizing to get an exact answer for your inputs.
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