Jon came within a couple of days to diagnose a fault with my 20yr-old Vaillant boiler. As there was more than one problem and likely to be further faults developing with age (also current parts delivery delays) he recommended a new boiler and fitted us into his work schedule within the week, on a Sunday, all for a very reasonable price. A water hammer suppression valve included. The finish is neat, all packaging and debris has been cleaned away, and the heating system immediately works well.