Heat Pump Sizing for 308 m² (3,315 sq ft) — US Sunbelt & Mediterranean (TX/FL/CA/ES/IT)
Thermal heat loss calculation, recommended heat pump capacity (kW, BTU/h & HVAC Tons), SCOP efficiency, and annual electricity consumption.
Recommended Heat Pump15.0 kW51,182 BTU/h (4.27 Tons)
Annual Electricity Usage4,912 kWh/yrDelivers 21,615 kWh Heat (SCOP 4.4)
Savings vs Direct Electric16,703 kWh/yrSpecific Load: 46.8 W/m²
Electrical Circuit (230V)25 A BreakerPeak Compressor Input: 4.17 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 Sunbelt & Mediterranean (TX/FL/CA/ES/IT) |
| Building Insulation Envelope | Standard Double-Glazed Insulation (55 W/m² Base) (46.8 W/m² Peak) |
| Peak Space Heating Load | 14.41 kW Thermal |
| Recommended Heat Pump Output (Incl. DHW) | 15.0 kW (51,182 BTU/h · 4.27 Tons) |
| Seasonal Coefficient of Performance (SCOP) | 4.4 (340%–450% Seasonal Efficiency) |
| Annual Heat Demand vs Electricity Consumed | 21,615 kWh Heat → 4,912 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 Standard Double-Glazed Insulation (55 W/m² Base) in US Sunbelt & Mediterranean (TX/FL/CA/ES/IT), the peak space heating load is 14.41 kW (46.8 W/m²). Including domestic hot water allowance, a 15.0 kW (51,182 BTU/h / 4.27 Ton) heat pump is recommended.
How many kWh of electricity does a 15.0 kW heat pump use per year?
With a Seasonal Coefficient of Performance (SCOP) of 4.4 over 1500 full-load equivalent heating hours, the heat pump consumes approximately 4,912 kWh of electricity per year to deliver 21,615 kWh of heat — saving 16,703 kWh/year compared to direct electric radiators.
Compare Other Home Sizes & Climate Zones
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