Hi,
I have an economy 7 hot water system with 2 immersion heaters (overnight and top-up), both of which have stopped working at the same time. The light on the top-up switch is coming on, so power is reaching the switch, and none of the fuses have tripped. I also had both immersion heaters replaced less than a year ago, so they are unlikely to be corroded.
Can anyone suggest a reason why both immersions have stopped working at the same time?
Many thanks...