An adequate supply of pure water on tap is one of the prerequisites of modern living. Hot water systems are undergoing a technological change with the introduction of unvented water systems over the more traditional copper cylinder. The advantages of these systems are mains pressure to both hot and cold draw off points (i.e.) taps, baths and showers, therefore no more header tanks and pipework in the loft space. All aspects of work undertaken, repairs, upgrades and replacements, whatever their size or nature.