How a Heat Pump Moves Heat Through Your Home

Heat pumps work by absorbing heat from the outside air, boosting it to a usable temperature, and releasing it into your home. This simple cycle runs continuously to provide steady, efficient warmth.

The Four-Step Cycle

Evaporator

Absorbs heat from the outside air, even in cold weather.

Compressor

Compresses the refrigerant, raising its temperature.

Condenser

Releases heat into your radiators or underfloor heating.

Expansion Valve

Drops the refrigerant pressure so it can absorb heat again.

Efficiency Explained Simply

Heat pumps are efficient because they move heat rather than generate it. A typical air-source heat pump might have a Coefficient of Performance (COP) of 3:

• 1 unit of electricity in → 3 units of heat out

This means lower running costs and better energy use compared to traditional boilers.

What This Means for Your Home

• Steady, low-temperature heating feels more consistent than on-off boiler cycles.
• Radiators may feel cooler to the touch, but your home stays warm.
• Works best with good insulation and larger radiators or underfloor heating.

Visual Diagram

Why This Matters

Understanding the heat pump cycle helps homeowners:

• Feel confident about how the system works
• Understand why heat pumps are efficient
• Know what to expect in terms of comfort and performance