Installing a ground source or water source heat pump system does not usually need planning permission and should fall within permitted development rights.
If you live in a listed building or a conservation area, however, you should contact your council to check on local policy.
Installation of one air source heat pump is normally permitted, provided that it complies with the relevant standards. In addition, there are restrictions on what kind of roof an air source heat pump may be installed, and air source heat pumps must be sited to cause minimal visual impact. For more details on restrictions applying to the installation of air source heat pumps, you should contact your local planning authority.
Disclaimer - Wales
This is an introductory guide and is not a definitive source of legal information. This guidance relates to the planning regime for Wales. Policy in England may differ. If in doubt contact your Local Planning Authority.