We have a heated towel rail in the bathroom. It is controlled by an electronic time switch in the same cupboard as the consumer units just outside the bathroom door. It's difficult to see the LCD on the timer so it's difficult to tell if you are switching it on or off when pressing the override button. There is a connecting block on the wall adjacent to the heater, which has shrouded screws so that no metalwork is visible externally, I've fitted a neon indicator inside the block and it's just about visible through the plastic, as long as the light level is not too high. Would it be permissible to fit the sealed plastic indicator through the wall of the block. If the drilled hole was a tight fit and the back of the head was bedded in sealant before tightening the locking ring, the integrity of the insulation shouln't be compromised.
The question isn't can it be done, but would it be permitted.
The question isn't can it be done, but would it be permitted.