Heat Loss Calculator

Estimate whole-house design heat loss and right-size a heat pump using the simplified UA method, infiltration, climate design temperature, and component breakdown.

Default heat-loss example

  • Design heat loss: 22,589 BTU/hr
  • Recommended heat pump: 24,000 BTU/hr (2-ton)
  • Total UA: 322.7 BTU/hr·°F
  • Annual heating: ~3,783 kWh at COP 3

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