What does it look like? Can you describe it for me please.
The is a white rectangular box on the side of the cylinder (Danfloss). There is a round silver box on the top of the cylinder with a red button it. There is a thermastat type box on the wall (immerstat). They all have wires going into them.
No there is no lever on that box.
No I dont see an AB on any of the boxes that are in the airing cupboard.
See earlier. There is no sign of AB on any of the boxes
Nothing that looks like this?
Ok, there is are 2 boxes like that but it is not in the airing cupboard. It is downstairs close to the boiler. The are attached to the pipes.