Heat Transfer Equation:
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The heat transfer equation (Q = U × A × ΔT) calculates the rate of heat gain or loss through a building surface. It's fundamental for HVAC design, insulation evaluation, and energy efficiency calculations.
The calculator uses the heat transfer equation:
Where:
Explanation: The equation shows that heat transfer increases with higher U-values (poorer insulation), larger surface areas, and greater temperature differences.
Details: Accurate heat transfer calculations are essential for proper HVAC system sizing, energy efficiency assessments, building code compliance, and insulation effectiveness evaluation.
Tips: Enter U-value in BTU/h-ft²-°F, area in square feet, and temperature difference in °F. All values must be positive numbers.
Q1: What is U-value?
A: U-value measures how well a building element conducts heat. Lower values indicate better insulation.
Q2: How does this relate to R-value?
A: R-value is insulation's resistance to heat flow (R = 1/U). Higher R-values mean better insulation.
Q3: What's a typical U-value for windows?
A: Single-pane windows might be 1.0-1.2, while double-pane low-e windows can be 0.3-0.5.
Q4: How to calculate annual heat loss?
A: Multiply hourly heat loss by heating degree days and hours per day, adjusting for thermostat settings.
Q5: Does this account for air infiltration?
A: No, this calculates conductive heat transfer only. Air leaks require separate calculations.