Technical Booklet P Sanitary Appliances Unvented Hot Water Storage and Scalding·Page 13·2.7
Control on Heating Sources
Devices controlling heating sources should be supplied by the manufacturer as part of the unit or package and comply with specific paragraphs, though indirectly heated systems with a boiler may have the thermal cut-out on the boiler itself.
Devices to control the heating source or sources should be supplied by the manufacturer as part of the unit or package, and should comply with paragraphs 2.9 and 2.10.
However, an indirectly heated system, which incorporates a boiler, may have the thermal cut-out on the boiler.
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