Heat Pump Sizing for 308 m² (3,315 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 Pump34.6 kW118,060 BTU/h (9.84 Tons)
Annual Electricity Usage23,335 kWh/yrDelivers 81,672 kWh Heat (SCOP 3.5)
Savings vs Direct Electric58,337 kWh/yrSpecific Load: 110.5 W/m²
Electrical Circuit (230V)70 A BreakerPeak Compressor Input: 12.81 kW
Thermal & Electrical Specification Table (308 m² / 3,315 sq ft)
| Heated Floor Area | 308 m² (3,315 sq ft) |
| Climate Zone & Design Outdoor Temp | US North & Canada Cold (-18°C Design, NY/IL/MI/ON) |
| Building Insulation Envelope | Older Uninsulated Building (85 W/m² Base) (110.5 W/m² Peak) |
| Peak Space Heating Load | 34.03 kW Thermal |
| Recommended Heat Pump Output (Incl. DHW) | 34.6 kW (118,060 BTU/h · 9.84 Tons) |
| Seasonal Coefficient of Performance (SCOP) | 3.5 (340%–450% Seasonal Efficiency) |
| Annual Heat Demand vs Electricity Consumed | 81,672 kWh Heat → 23,335 kWh Electricity |
Frequently Asked Questions
What kW size heat pump do I need for a 308 m² (3315 sq ft) house?
For a 308 m² (3315 sq ft) building with Older Uninsulated Building (85 W/m² Base) in US North & Canada Cold (-18°C Design, NY/IL/MI/ON), the peak space heating load is 34.03 kW (110.5 W/m²). Including domestic hot water allowance, a 34.6 kW (118,060 BTU/h / 9.84 Ton) heat pump is recommended.
How many kWh of electricity does a 34.6 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 23,335 kWh of electricity per year to deliver 81,672 kWh of heat — saving 58,337 kWh/year compared to direct electric radiators.
Compare Other Home Sizes & Climate Zones
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