They do look noisy don’t they; is how I normally respond when a customer asks me that question – and they always do! There is a wide range in sound performance of heat pumps on the market today. You definitely get what you pay for in sound quality.
With modern high quality air source heat pumps, noise should not be a significant concern.
Noise is such a subjective issue. Does 42dB(A) mean anything to you?
Me neither. Every person hears things differently, so the best advice I can give is to stand next to one and listen for yourself. For me personally, I think a good quality air source heat pump is no louder than the roar of an external flue from a gas or oil boiler.
Here is a nice infographic to demonstrate the sound of an air source heat pump relative to more familiar noises in the home.
The real question being considered is “where should we put it”? The shorter the distance from the external air source heat pump unit to the internal equipment the better, as this minimises any potential heat losses. Therefore the quieter the system, the more options you have for location, without disturbing you or your neighbours. Below is a useful video to explain the issue.
Another key sound issue, relates to planning permission. Air source heat pumps normally do not require planning permission, since rules were changed, granting permitted development rights under certain conditions.
Find out more information on this here: //www.gov.uk/government/publications/permitted-development-rights-for-householders-technical-guidance
Surprisingly, noise can be more of a concern to customers in very quiet rural locations with minimal background noise, than homeowners in an urban environment with closer neighbours, but higher levels of background noise such as traffic.
Of course, one of the key benefits of ground source heat pumps is that you avoid this issue completely.