Heat Pump Sizing for 124 m² (1,335 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 Pump4.3 kW14,672 BTU/h (1.22 Tons)
Annual Electricity Usage1,261 kWh/yrDelivers 5,550 kWh Heat (SCOP 4.4)
Savings vs Direct Electric4,289 kWh/yrSpecific Load: 29.8 W/m²
Electrical Circuit (230V)10 A BreakerPeak Compressor Input: 1.19 kW
Thermal & Electrical Specification Table (124 m² / 1,335 sq ft)
| Heated Floor Area | 124 m² (1,335 sq ft) |
| Climate Zone & Design Outdoor Temp | US Sunbelt & Mediterranean (TX/FL/CA/ES/IT) |
| Building Insulation Envelope | Modern / New Build Insulation (35 W/m² Base) (29.8 W/m² Peak) |
| Peak Space Heating Load | 3.7 kW Thermal |
| Recommended Heat Pump Output (Incl. DHW) | 4.3 kW (14,672 BTU/h · 1.22 Tons) |
| Seasonal Coefficient of Performance (SCOP) | 4.4 (340%–450% Seasonal Efficiency) |
| Annual Heat Demand vs Electricity Consumed | 5,550 kWh Heat → 1,261 kWh Electricity |
Frequently Asked Questions
What kW size heat pump do I need for a 124 m² (1335 sq ft) house?
For a 124 m² (1335 sq ft) building with Modern / New Build Insulation (35 W/m² Base) in US Sunbelt & Mediterranean (TX/FL/CA/ES/IT), the peak space heating load is 3.7 kW (29.8 W/m²). Including domestic hot water allowance, a 4.3 kW (14,672 BTU/h / 1.22 Ton) heat pump is recommended.
How many kWh of electricity does a 4.3 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 1,261 kWh of electricity per year to deliver 5,550 kWh of heat — saving 4,289 kWh/year compared to direct electric radiators.
Compare Other Home Sizes & Climate Zones
60 m² (646 ft²) Heat Pump80 m² (861 ft²) Heat Pump100 m² (1076 ft²) Heat Pump120 m² (1292 ft²) Heat Pump140 m² (1507 ft²) Heat Pump160 m² (1722 ft²) Heat Pump180 m² (1938 ft²) Heat Pump200 m² (2153 ft²) Heat Pump250 m² (2691 ft²) Heat Pump300 m² (3229 ft²) Heat Pump124 m² in Nordic / Scandinavia124 m² in Central Europe / DACH124 m² in UK & Temperate Maritime124 m² in US North & Canada Cold124 m² in Australia & Mild APAC