fan overrun issue

[studentspark]

airflow quiet air 100 fan


https://www.airflow.com/productdetail_/pg_QUIE/9041260

https://www.airflow.com/AIR1/AIR1-TEST/pdf/QuietAir/9041260_QuietAir_QT100T.pdf


Will not over run, switches on with the light, but will not overrun when light off.

Permanent live and switch live are correct and in the right terminal

Fan works when I wired it in garage to test it, but when on the lighting circuit will not work.
Any thoughts

 

[AndyPRK]

Adjust the timer?

 

[GaryGarden]

What voltage do you have at the permanent live when the lamp is off?

Are you sure you haven't got two switched live by mistake?

 

[studentspark]

It works fine on the bench but not in situ.

 

[EFLImpudence]

Permanent live and switch live are correct and in the right terminal

What about the other end ???

 

[studentspark]

No, 230v to live with light off

230v to switch live when on and 0 v when off

At the other end - live goes to perm. switch to switch neutral to neutral

As I say work when I test the fan to see if it was faulty, just not on the lighting circuit.

 

[JohnW2]

It works fine on the bench but not in situ.

In that case, isn't almost certain that your 'in situ' wiring is not delivering L and S/L to the correct terminals at the correct times? ... I would think it extremely likely that you have got the L and S/L connections to the fan swapped - that would result in what you're experiencing.

Kind Regards, John

 

[studentspark]

Indeed, but I've checked and checked and checked.
Somethings not right though
Perm is always live and switch switches !

 

[AndyPRK]

Try removing the bulb or fit a traditional bulb

 

[studentspark]

GU10 lamps.
Curious as to what removing the bulbs will do?

I think it may be a neutral issue, but it does not appear that the neutral is being switched somehow

 

[JohnW2]

Indeed, but I've checked and checked and checked. Somethings not right though Perm is always live and switch switches !

Fair enough - but why don't you just try (if you haven't already) swapping the L and S/L connections to the fan (it can't do any harm).

Kind Regards, John

 

[studentspark]

yes done that, still does not work

 

[EFLImpudence]

Could you have done anything while testing to have fried the timer?

 

[JohnW2]

yes done that, still does not work

On the basis of everything you've told us, the only explanation I can think of (apart from a faulty timer module - but even that's not possible if, as you say, it still works 'as expected' on the bench) is that the light switch is switching the neutral - but you've said that you don't think that is the case, either.

Is it possible for you to check whether switching the switch off results in the voltage between the S/L conductor and earth disappearing?

Kind Regards, John

 

[studentspark]

Yes switch live has 230v to earth when on and 0v to earth when off.

Timer works fine when testing so I don't think I've fried it

Thanks