Technical Booklet P Sanitary Appliances Unvented Hot Water Storage and Scalding·Page 13·2.6
Certification of Unvented Hot Water Storage Systems
Unvented hot water storage systems must be certified by an accreditation body as complying with BS EN 12897, and must include controls over heating sources, tundishes, and discharge pipes meeting specified requirements.
by a certification body having National Accreditation Council for Certification Bodies (NACCB) accreditation as complying with BS EN 12897;
(c) have controls over the heating source or sources complying with paragraph 2.7;
(d) have a tundish or tundishes complying with paragraph 2.13; and
(e) have a suitable discharge pipe or pipes complying with paragraphs 2.14 to 2.17.
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