Hi all, first year in our new home which uses oil. In the summer we used elec only. In the winter we got some oil delivered and used that. The oil has just run out so I switched the immersion heater back on but we now have no heating but we do have hot water? The only thing I can think of is maybe the valve is dead but it seems too much of a coincidence that its packed up at the same time we run out of oil. Any suggestions on what you think this could be? thanks in advance! EDIT: forgot to add that when the oil ran out we had neither hot water or heating (obviously). UPDATE: I've just tested both of the motorised valves after watching a youtube video. They both appear to be working correctly. ie. resistance when its off. Both behave the same. I am completely baffled! UPDATE 2: even with hot water and heating on, pipes are cold both sides of both valves. The only hot pipes I can find branch off from the top of the immersion tank.