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    BTU

    Definition

    A BTU, or British Thermal Unit, is the amount of heat required to raise one pound of water by one degree Fahrenheit, used to measure heating and cooling capacity.

    What BTU Means for Your Business

    What it means

    BTUs are the universal unit of heat in HVAC and appliance work. Furnaces, air conditioners, water heaters, and space heaters are all rated in BTUs per hour, which measures how fast they move heat in or out of a space.

    Why it matters

    Proper BTU sizing is critical. Too small and the equipment runs constantly without keeping up. Too big and it short cycles, wasting energy and wearing out faster. Good techs calculate BTU loads before recommending any equipment.

    How contractors use it

    Installers perform load calculations based on square footage, insulation, window area, climate zone, and orientation. The load calc drives the BTU rating needed, which drives the equipment selection.

    Real-World Example

    An HVAC company resized a 2,400 sq ft home's system from 4 tons (48,000 BTU) to 3 tons (36,000 BTU) after a proper load calc. The right-sized install cost the customer $2,100 less and runs 30% more efficient.

    Put This Into Practice with Free Software

    Kaldr Tech handles btu and everything else you need to run your shop. $0/month, 3.5% + 30¢ per transaction.