Hi Guys, first time post but always been interested viewer. Trying to understand how to provide off peak supply to flat conversions without sending a 4 core Submain . got a good understanding (so far - been 20 years since last carried out) that you can wire through a signal wire at origin and use contactor to connect the load . Just need futher clarification of the principles of this method as the benifits our obvious to ourselves and client. Also any experiance of these electric combi boilers ( got good understanding so far - nobody else i know has heard of them). Any feedback would be gratefuully appreciated !