Need advice from an electrition please

[c0sie]

I have an electric water heater/tank thingy stuck away in my cupboard here in the flat. It works on the Energy7 system. Two lots of switches work this heater, the bottom switch turns the thing on ready for the Energy7 thing to kick in at 1am, and the top switch turns it on whenever I need more hot water.

Anyways...although the bottom switch is on and does light up at 1am (I checked this morning), the water heater part isnt heating and hasnt heated for 2 days now (brrr...)

Any electritions able to offer any advice at all?

I know ill probably need to call a sparky out soon enough for this but id like to hear any ideas as to the problem and potential cost to fix it

Thanks in advance

Cold Cris...