hello,
we have an immersion heater which is hooked up with 2 switches because of economy 7 electricity. Recently we have not been getting hot water from about 3pm (the switch for the top up element is on with a red light). we called in a plumber who took a look at it and tried to blame it on the economy 7 side of things and that he could not do anything because he was not an electrician, he did not seem to really check out the heater much.
Does this sound like a plumbing issue or an electric one?