All that will tell you, if it works, is that your off-peak supply has started, and I didn't think there was any question about that.As the unit is all Economy 7 I'll have to wait until after 1am to put my testing screwdriver on the mcbs.
If flameport's guess is right they'll be one storage heater and one immersion.Then, I'll turn off the two on the left, which are labelled B16 (the others are B20) and see if I can track down some devices which are n't working.
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