The Building Regulations in England and Wales make it a legal requirement for the appropriate Local Authority (LA) to be informed about the installation of a heat producing gas appliance e.g. boiler or fire.
Only a Gas Safe registered engineer can fit a new gas appliance. Once a gas appliance has been installed it can only be notified by a Gas Safe registered engineer.
If you have a new gas appliance fitted your Gas Safe registered engineer should let your LA know. Registered engineers have responsibility for complying with the Building Regulations but the owner of the property is ultimately the one who may be the focus of enforcement action by the LA if the work is not notified.