3 calculators

Electrical & HVAC calculators

Size the systems behind the walls: wire gauge from amps, distance and voltage drop, air-conditioner capacity in BTU, and solar system size, panel count and payback.

Wire Size CalculatorAWG wire size by amps, distance and voltage drop (NEC tables). BTU CalculatorAir conditioner size in BTU for any room (ENERGY STAR method). Solar Panel CalculatorSolar system size, number of panels, roof space and payback.

Electrical and HVAC sizing has safety and code implications — use these tools for planning and confirm with a licensed professional.

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