Fan wiring help please.

[defblade]

I've replaced the standard little wall fan (which worked ok and had a timer off delay, but wasn't really man enough) our bathroom came with with a posh ventaxia centrifugal thing, which is supposed to have light switch timer on delay, timer off delay, humidity control and an over-ride pull switch.

I checked it was running ok on the kitchen side with a lead into a socket (jumping the light-switch supply from live) and it worked fine, also removing the jump and using the override switch it was fine.

Installed fan, extending and taking careful note of the original wiring (I've installed fans from scratch before so wasn't expecting trouble.....)

Switched the electric back on, and the fan started running instantly without the lights on. Override switch made no difference. Switched electric off again, thought maybe I'd swapped live and switched live by accident, so changed them over. Fan now runs when the light is on, but not otherwise (over ride doesn't work) and the timer on and off don't trigger - it just goes on and off with the light. So I've left it like that for now.

Getting the multimeter out, I've got (these are the marked positions on the terminal block, not which wire I think is which, if you see what I mean):

Light and fan OFF: L-N 0v, N-LS 240v, L-LS 240v
Light and fan ON : L-N 240v, N-LS 240v, L-LS 0v

So between neutral and live-switched I've got a permenently live circuit which is obviously not right.


I've bought a neon screwdriver but after reading stuff on here, I'm too nervous to use it ..... is there any sensible way of using a multimeter to see what each individual wire does? Or can anyone work it out from the above?

Thanks in advance

 

[sparkyspike]

I think you had it wired up right to start with. Put it back as it was - if it still runs with the light switch off, let it run on and see if it stops. You can adjust the timer.

If it doesn't stop, you may have a faulty humidistat. (Is your kitchen humid?!) You can disconnect the humidistat and try again.

 

[defblade]

It's a bathroom, and it had occured to me that it could be the humidity sensor (it's always been a bit dampish in there, hence upgrading the fan) but it was just normal that evening. I was going to try it with the sensor turned right down.

But a good idea to see if the fan runs on with the off delay! Will try that tomorrow, thanks.

 

[defblade]

Well, I didn't get around to it for a bit, but you were spot on Sparkyspike - once it had run through the off-delay once, prefect behaviour. Cheers!