Hot water tank not heating up

[KernowB]

I have a hot water tank heating by overnight low cost electricity. However, at the weekend I noticed the water wasn't getting hot, so I've only been using it with the "boost" control when I need hot water. I've noticed that the panel next to the heater with the "On switch, Boost etc" gets hot over the 30mins the boost is working. I'm now very worried that it may catch fire so have it switched off & am using my kettle for hot water which is rubbish! I've no idea what could be wrong, whether I need a plumber or electrician and as i'm on my own I'm afraid of getting "ripped off". I'd be extremely grateful for any help or advice you can give me. Is it likely to be the tanks element, thermostat or what?????
Many thanks for any help.

 

[jam1979]

I take it ur on economy 7 with 2 elements it could be ur bottom 1 has gone but u would need a plumber 2 check this and replace accordingly as the top 1 is ur boost and only heats up the top part of ur cylinder