Technical Booklet P Sanitary Appliances Unvented Hot Water Storage and Scalding·Page 14·2.10
Thermal cut-out wiring for indirectly heated systems
Non self-resetting thermal cut-outs in indirectly heated systems must be wired to an approved motorised valve or device capable of shutting off flow to the primary heater, or alternatively the cut-out may be located on an incorporated boiler.
Where the system is indirectly heated the non self-resetting thermal cut-out should be wired to a motorised valve or some other device which is –
(a) approved by a member of EOTA; or
(b) approved by a body having NACCB accreditation,
as being capable of shutting off the flow to the primary heater.
However, an indirectly heated system, which incorporates a boiler, may have the thermal cut-out on the boiler.
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