We have an arrangement (uk.d-i-y passim) for switching the fan on in the bathroom.
There is a humidistat with a pull switch so you can have the fan come on when the humidity is high, or you can force it on when the atmosphere needs clearing.
There is a second unit - a run on timer - which is activated by power from the humidistat so that whatever switches the fan on (humidity or switch) via the humidistat the timer then runs on after the power is switched off again.
Same components and set up in two bathrooms.
This all works fine.
However the humidistat has a neon and the run on timer has a neon. I would expect both to come on when there is power via the humidistat and then the humidistat neon to go off, followed a while later by the timer neon.
However the humidistat neon never comes on, although the timer neon always comes on.
The importance of the humidistat neon is to indicate if the humidistat is still powered on (for instance if you have used the pull switch then not turned it off) or if the run on timer is all that is keeping the fan on.
All wired in by our sparky, who generally seems to know what he is doing, but can't think why the neon isn't working.
It seems unlikely that it is a faulty unit as we have two units and both show the same behaviour.
Any suggestions welcome.
Thanks
Dave R