Technical Booklet P Sanitary Appliances Unvented Hot Water Storage and Scalding·Page 17·3.3
Acceptability of in-line blending valves
In-line blending valves must comply with relevant harmonised European Standards such as BS EN 1111 or BS EN 1287, demonstrating that 48°C cannot be exceeded and that the product fails safely without discharging water above the maximum temperature.
The acceptability of in-line blending valves can be demonstrated by compliance with the relevant harmonised European Standard such as BS EN 1111 or BS EN 1287 to demonstrate that the maximum temperature of 48 ºC cannot be exceeded in operation and that the product will fail-safe (i.e. not discharge water above the maximum temperature). Such valves should not be easily altered by building users.
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