What is a vented hot water storage system?

Vented (open) hot water storage system means a vessel fed with cold water from a dedicated storage cistern. Expansion of the water when it is heated is accommodated through the cold feed pipe. A vent pipe connecting the top of the vessel to a point open to atmosphere above the cold water storage cistern is provided as a safety device.

What is Unvented hot water storage system?

Unvented (closed) hot water storage system means a vessel fed with cold water from a supply pipe or dedicated storage cistern (without a vent pipe) and in which water is heated directly or indirectly.

Who should install an Unvented hot water storage system?

To meet the requirements of the regulation, installation of an unvented system should be undertaken by a “competent installer”. All installations of unvented hot water storage systems having a capacity of more than 15 litres should be notified to the relevant Local Authority by means of building notice or by the sub-mission of full plans.

What is a hot water storage system unit?

Hot water storage system unit means a hot water storage system having the safety devices described in 3.10 and 3.17 and all other applicable operating devices factory fitted by the manufacturer.

What is a hot water storage system package?

Hot water storage system package means a hot water storage system having safety devices described in 3.10 and 3.17 of the Approved Document factory-fitted by the manufacturer, together with a kit containing other applicable devices supplied by the manufacturer to be fitted by the installer.

What is the inlet control group?

Table 3.1 and worked example The inlet control group contains a pressure reducing valve, pressure relief valve, connection to the expansion vessel, cold water balanced connection and can also include a single check valve all in the one manifold. There are two basic dangers that unvented systems must address.