BS 3198:1981

This standard BS 3198:1981 Specification for copper hot water storage combination units for domestic purposes is classified in these ICS categories:

• 91.140.60 Water supply systems

This British Standard specifies requirements for direct, double feed indirect and single feed indirect types of combination hot water storage units having hot water storage capacities in a series of ranges between 65 litres and 210 litres, in which, when water is drawn off from the hot water storage vessel, there is automatically:

1. replacement of water withdrawn by that from a cold water feed cistern incorporated in the unit and adjacent to the hot water vessel; and
2. controlled replacement of the water in the cold water feed cistern from the water supply by means of a float operated valve.

NOTE The preferred hot water storage capacities are 85, 115, 130, 140, 150, 180 and 210 litres.

Requirements for direct, double feed indirect and single feed indirect types of units having hot water storage capacities of between 65 litres and 180 litres.