I'm a Worcester Bosch accredited and highly experienced, time served (since 1989) central heating and boiler engineer. I'm able to repair, service and install all makes of boiler. With Worcester accreditation I can provide a 10 or 12 year guarantee on Worcester Bosch boilers and controls! If your boiler is getting on a bit, perhaps approaching 10 years old or so, you really would benefit from replacing your boiler system with a modern, condensing combi (combination) or conventional boiler and the latest controls.