I want to service my boiler and require any recommendations in Bristol. I stumbled on to this company Willow & Matthews Plumbing & Heating Ltd; their websites description outlines services available as: boiler service bristol , boiler repairs, installations & replacement. I want a reliable and skilled engineer I know will know all of the things to check during the inspection of my boiler so that I may maintain its functionality. What kind of things would I search for when deciding on which heating company to use?