Technical Booklet P Sanitary Appliances Unvented Hot Water Storage and Scalding·Page 13·2.8
Systems with a Storage Vessel Over 500 Litres or Over 45 kW
Large unvented hot water storage systems with capacity exceeding 500 litres or power input exceeding 45 kW are typically individual designs for specific projects and must comply with BS 6700+A1 or BS EN 12897.
An unvented hot water storage system, whether heated directly or indirectly, having a storage vessel which has a capacity of more than 500 litres or a power input of more than 45 kW will generally be an individual design for a specific project.
The system should generally comply with BS 6700+ A1 or BS EN 12897, as qualified by paragraphs 2.9 to 2.13.
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