Central Heating Installations - choosing an installer
There are many good installers who provide a professional service. I would choose one who is registered with CORGI and Phoenix for gas installations or OFTEC for oil heating systems.
Get a few quotes from different installers to compare prices but do compare like for like. If one quote offers to install a
magnetic filter, powerflush the system and introduce an inhibitor, make sure the other quotes include the same.
Finally listen to advice as regards safety and act upon it. The first priority for an engineer is your safety, then the efficiency of the heating system.