Heat Pump Sizing for 420 m² (4,521 sq ft) — US North & Canada Cold (-18°C Design, NY/IL/MI/ON)
Thermal heat loss calculation, recommended heat pump capacity (kW, BTU/h & HVAC Tons), SCOP efficiency, and annual electricity consumption.
Recommended Heat Pump19.7 kW67,219 BTU/h (5.6 Tons)
Annual Electricity Usage13,104 kWh/yrDelivers 45,864 kWh Heat (SCOP 3.5)
Savings vs Direct Electric32,760 kWh/yrSpecific Load: 45.5 W/m²
Electrical Circuit (230V)40 A BreakerPeak Compressor Input: 7.3 kW
Thermal & Electrical Specification Table (420 m² / 4,521 sq ft)
| Heated Floor Area | 420 m² (4,521 sq ft) |
| Climate Zone & Design Outdoor Temp | US North & Canada Cold (-18°C Design, NY/IL/MI/ON) |
| Building Insulation Envelope | Modern / New Build Insulation (35 W/m² Base) (45.5 W/m² Peak) |
| Peak Space Heating Load | 19.11 kW Thermal |
| Recommended Heat Pump Output (Incl. DHW) | 19.7 kW (67,219 BTU/h · 5.6 Tons) |
| Seasonal Coefficient of Performance (SCOP) | 3.5 (340%–450% Seasonal Efficiency) |
| Annual Heat Demand vs Electricity Consumed | 45,864 kWh Heat → 13,104 kWh Electricity |
Frequently Asked Questions
What kW size heat pump do I need for a 420 m² (4521 sq ft) house?
For a 420 m² (4521 sq ft) building with Modern / New Build Insulation (35 W/m² Base) in US North & Canada Cold (-18°C Design, NY/IL/MI/ON), the peak space heating load is 19.11 kW (45.5 W/m²). Including domestic hot water allowance, a 19.7 kW (67,219 BTU/h / 5.6 Ton) heat pump is recommended.
How many kWh of electricity does a 19.7 kW heat pump use per year?
With a Seasonal Coefficient of Performance (SCOP) of 3.5 over 2400 full-load equivalent heating hours, the heat pump consumes approximately 13,104 kWh of electricity per year to deliver 45,864 kWh of heat — saving 32,760 kWh/year compared to direct electric radiators.
Compare Other Home Sizes & Climate Zones
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