Are heat pumps noisy?

A common question for anyone considering a transition to renewable or low-carbon heating is: “Are heat pumps noisy?” Put simply, the answer would be “no” especially when installed and maintained correctly.

Air-to-water heat pumps have an outdoor unit that contains a compressor and fan, which are responsible for extracting heat from the outside air and transferring it into your home. These components do make some sound during operation, typically between 40 and 60 decibels (dB) depending on the size of the heat pump, which is comparable to everyday background noise. For example, a modern fridge-freezer would operate at 40-45 dB.

Several factors can influence how much noise you notice from a heat pump:

Installation – Proper placement and installation help reduce vibration and sound. An incorrectly installed unit may be noisier than it should be.
Maintenance – Like any appliance, a well-maintained heat pump will run more quietly. Blocked fans or worn parts can increase noise.
Model and size – Larger systems or those working at full capacity (especially in colder weather) may generate slightly more noise.