Technical Booklet P Sanitary Appliances Unvented Hot Water Storage and Scalding·Page 12·2.2
Approach to safety devices: energy cut-out and relief valve
One acceptable approach combines a non self-resetting energy cut-out to prevent overheating with a temperature relief valve or combined temperature and pressure relief valve to safely discharge water during serious overheating.
One approach might consist of –
(a) a non self-resetting energy cut-out to disconnect the supply of heat to the storage vessel in the event of the storage system overheating; and
(b) a temperature relief valve or a combined temperature and pressure relief valve to safely discharge the water in the event of serious overheating.
Alternative approaches that provide an equivalent degree of safety may be acceptable.
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