Thread Size : DN32 / BSP 1.1/4" / 42mm. 48 volt systems produce up to 1000W of heat, but can be used with a 24 volt system to produce 250W or 12 volt to produce 62W. Easily fitted by a competent DIY enthusiast : just isolate your heating system, close water inlet/stop cock, open a hot water escape/tap to drain the boiler down a bit and any header tank feed to below surface of the inlet (normally at the top of the tank).
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