Humity fan wiring????

[parsman]

Hi,
I'm trying to get a screwfix humidity model fan working properly but I can't seem to do so. The set up I have is a cable supplying the fan from the mains, where I have a 13A fused switched connection unit outside the bathroom. There are three terminals inside the fan, T1 (switched live supply), T2 (live perm supply) and T3 (neutral). When I attach live to T1, the red LED on the unit lights up and the fan continues to run and is only switched off from the outside FSC. When I try live to T2, the LED is not lit up, but the fan continues to run and adjusting the control knob on the unit for the relative humidity level does not turn off the unit, only when I turn it to the OFF position does it switch off. The humidity adjustment knob seems not to work....

Any ideas???

Thx
Pars.

 

[HandyJon]

The clue is in the words switched live and permanent live. The permanent live is wired in to live, the switched live is wired to the live in your light switch (or a seperate switch). The fan is designed to work and sense humidity only when the light is on. That way it doesn't come on in the middle of the night. So in normal use the fan will only start after the light has been turrned on AND the humidty reached the preset level, and then it will run for a set time (5-20mins) after the light has been turned off.

 

[breezer]

to add to the above you need to rewire your fan, so it has as mentioned, live, switched live and neutral, but to get a switched live (when light is on), i ask where the fcu is fed from, if the ring, then leave the fcu and whire the fan from the lighting circuit, because if you dont you will get a back feed from the lights io the ring circuit which is very dangerous.


there is a drawing in the for refernce section, its not a humidity fan, but the wiring is the same

 

[parsman]

First of all a quick correction of my original posting:
When Live wire is connected to Switched Live, the red LED on unit is lit, but the fan does not turn on even when there is lot of condensation (after a bath)....

The FCU, which I guess acts as an external switch is fed from the ring main. The thing is I would like the fan to be switched on all the time and not just when the lights are switched on(normally only during the night). At the mo, connecting to perm live terminal results in the fan just continuely running irrespective of humidity. So, what is the best way to wire the fan (always on but only activated when humidity level is past), considering cable is from a switched FCU that is fed from the main?

 

[parsman]

I eventually sent it back and got a pull cord humidity model (manrose). This just needs a Perm Live and Perm neutral. I connected it to a external FSC with a 3amp fuse, fed from lighting ring. Well, this model and set works fine.....

Parsman