There should be a seperat fuse box for the storage heaters. Each heater has a seperate fuse. You should check that one of these has not tripped.
The heater that doesnt work, has two seperate supplies. One for the convector, which is live all day to enable you to use this in the day time. The other supply is the cheaper night supply. This is the one with the problem.
If the fuse is ok, the likley culprit is the switch at the fused spur, or the fuse there, if one is fitted. These often stop working when switched back on.
You can check this, if there is no red neon, by turning off ALL poewer, then attaching a normal reading lamp to the connections where the heater attaches inside the spur.
This should then come on when the cheap rate electricity starts, normally about 11pm. If it doesnt, the problem is back towards the fuse box and is probably the fuse there
If you need more help, just ask
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