Cold Climate Heat Pump Sizing Calculator
Determine the minimum heating capacity (BTU/h) required for a cold climate heat pump based on your home's characteristics, insulation quality, and local design temperatures.
Formulas Used
1. Envelope Heat Loss (walls, windows, ceiling):
Q = U × A × ΔT
- ΔT = Tindoor − Toutdoor (°F)
2. Infiltration Heat Loss:
Qinf = 0.018 × ACH × Volume × ΔT
3. Total Design Load:
Qdesign = (Qwall + Qwindow + Qceiling + Qfloor + Qinf) × 1.15
4. Capacity in Tons:
Tons = Qdesign / 12,000 BTU/h per ton
5. COP at Design Temperature:
COP ≈ max(1.5, 4.0 − 0.05 × (47 − Toutdoor))