DIN Standards Committee Valves
Building valves - Expansion groups - Tests and requirements
Abstract
This document specifies, dimensions, materials and performance requirements (including methods of test) for expansion groups, of nominal sizes from DN 15 to DN 25, having working pressures1 from 0,1 MPa (1 bar) to 1,0 MPa (10 bar). Expansion groups are fitted to the cold potable water supply only for expansion purposes, e.g. of storage water heaters, having a maximum distribution temperature of 95 °C. Expansion groups limit pressure in the water heater to which they are fitted, that is produced by thermal expansion of the water, prevent the backflow of water into the supply pipe and prevent the discharged water to get into contact with the water in the water heater. Expansion groups do not control temperature and alone do not constitute the protection required for storage water heaters. NOTE The use of the device specified in this document does not override the need to use controls (e.g. thermostats and thermal cut-outs) which act directly on the power sources of water heaters (for more information see Annex A).
Begin
2025-05-13
WI
00164782
Planned document number
prEN 1488 rev
Responsible national committee
NA 003-02-02 AA - Valves for potable water supply in buildings
Responsible european committee
CEN/TC 164/WG 14 - Valves and fitting for buildings and devices to prevent pollution by backflow
previous edition(s)
Building valves - Expansion groups - Tests and requirements
2021-05
