Why a switched live fan is not switching on?

[ahlondon]

I understand the basics of live and neutral feeding a timed extractor and then switched live feeding that terminal. My builder has who say he's wired it up successfully before can't make it work. I would say neither him nor I are skilled enough to troubleshoot it but in the other bathroom when I asked a fully qualified niceic electrician to set up an extractor, she too could not get the switched live to operate it.

Other than all of us not doing the wiring correctly, could there be another reason why the fans are not operating as they should; maybe the cables/neutral/live are all mixed up in the lighting circuit?

 

[ETAF]

do you have a multimeter and know how to use for mains voltage 240V AC ???

 

[RandomGrinch]

You could remove the fan from the wall, connect a flex with plug (3A fused), connect the brown to permanent live, add a link wire between that and Timed, and see if the fan operates?

 

[ahlondon]

do you have a multimeter and know how to use for mains voltage 240V AC ???

I don't and have not seen my builder with one so i don't think extensive testing with know-how is going happen without a proper electrician

 

[ahlondon]

You could remove the fan from the wall, connect a flex with plug (3A fused), connect the brown to permanent live, add a link wire between that and Timed, and see if the fan operates?

The Xpelair fan is new and a second one has been tried. Are you saying I can replicate the switched live wiring by feeding from the live wire to the switched live terminal an don contact that would activate the fan (and when disconnected switch off after the timed period)?

 

[ETAF]

I don't and have not seen my builder with one so i don't think extensive testing with know-how is going happen without a proper electrician

Shame, as you would be able to test in situation and see if the Mains LIVE is Live and the switch Switched is live
then also test at the switch

An electrician would have one, in fact everyone will have, you mention builder , did he install then ???

They are pretty cheap for a DIYer in places like screwfix / toolstation , even argos etc

LAP DC Digital Multimeter 600V - Screwfix

Order online at Screwfix.com. Multimeter features large digital display with backlit LCD for easy use in dark environments. Data hold function captures and holds the display reading when disconnected. Ideal for testing and solving a variety of household electrical problems safely and accurately...

www.screwfix.com

A lot of DIYer will have one , for things like electrics , Cars etc
Do you have a neighbour who may have one to lend

 

[ahlondon]

Shame, as you would be able to test in situation and see if the Mains LIVE is Live and the switch Switched is live
then also test at the switch

An electrician would have one, in fact everyone will have, you mention builder , did he install then ???

They are pretty cheap for a DIYer in places like screwfix / toolstation , even argos etc

LAP DC Digital Multimeter 600V - Screwfix

Order online at Screwfix.com. Multimeter features large digital display with backlit LCD for easy use in dark environments. Data hold function captures and holds the display reading when disconnected. Ideal for testing and solving a variety of household electrical problems safely and accurately...

www.screwfix.com

A lot of DIYer will have one , for things like electrics , Cars etc
Do you have a neighbour who may have one to lend

Gosh that is cheap. For some reason I thought they cost so much more but maybe that's for a fancy one. The builder is completing the bathroom so hasn't finished installing. While I don't know if he really knows, the previous electrician couldn't make it work either. If it was found that something was not actually live (wires mixed up), what would be the course of action?

 

[Alec_t]

the previous electrician couldn't make it work either. If it was found that something was not actually live (wires mixed up), what would be the course of action?

Use a different electrician. A qualified one would be able to tell if wires had been mixed up.

 

[ETAF]

the previous electrician couldn't make it work either.

Get one who can , maybe on recommendation from neighbours
i would expect a GOOD builder - at least the ones i have dealt with over the years, and thats probably 4 in the last couple of years, know and use a competent electrician, and as i know a lot about electronics and electrics - as qualified many years ago , i can question and test

any reason why the electrician did not fix it (other than not a good electrician , maybe the sort that do really basic stuff for builder) - or give a plan of what may be required - seems strange , i would expect an electician to work out whats wrong and why, and if he/she cannot - give a number of options on how to resolve , and price

the course of action is to find out why its not working and put it right or at least give a report (maybe verbal) of what needs to be done

I thought they cost so much more but maybe that's for a fancy one.

yes for a more accurate and reliable machine , FLUKE would be a common make

any pictures
what type of switch in bathroom -

its pretty basic wiring for a fan

Extractor fan wiring - DIYWiki

flamport is also a member here with aa website

Electrical Information Pages

Electrical Information Pages concerning UK electrical installations in domestic and similar situations

flameport.com

i'll edit if i find the info

 

[boringoldcodger]

Are you saying I can replicate the switched live wiring by feeding from the live wire to the switched live terminal an don contact that would activate the fan

I believe RandomGrinch is suggesting that, as a test, you connect the Live and the Timer terminals together, also connect (via the plug) the Live terminal to 240v and the neutral terminal to 0v and see if the fan works.
I wouldn't suggest having a link wire connected at 1 end to the Live terminal and have the other end "flapping around in the breeze" and then touching the Timer terminal with that other end.

 

[Tigercubrider]

Is this in conjunction with the bathroom light?
Is it an LED lamp?

 

[RandomGrinch]

The Xpelair fan is new and a second one has been tried. Are you saying I can replicate the switched live wiring by feeding from the live wire to the switched live terminal an don contact that would activate the fan (and when disconnected switch off after the timed period)?

With a timer fan, if the timed and permanent live feeds are both supplied with power, the fan should operate.
Linking the two terminals simply makes the fan an on/off fan, with no overrun.
If you've proved the fans work (it still may be worth trying with a flex), use a short link wire to join the timed and permanent live connections together.
Then try and connect up the live and switched live in turn (safely isolating power and the other wire when connecting).
If the permanent live is working, the fan should turn constantly.
If the switched live is working, the fan should turn on and off with the switch.
If the fan doesn't work with either - look elsewhere!
The cable to a timer fan would usually be a 3 core + earth; are you sure you've got the grey, brown and black cores marked up correctly?

 

[Taylortwocities]

With a timer fan, if the timed and permanent live feeds are both supplied with power, the fan should operate.

Not if the neutral is broken!

 

[RandomGrinch]

Not if the neutral is broken!

Yes, hence the ...

If the fan doesn't work with either - look elsewhere!

 

[ahlondon]

Is this in conjunction with the bathroom light?
Is it an LED lamp?

Yes, with bathroom light which has an LED lamp. Builder keeps says maybe fans are too powerful for the circuit but I reminded him light bulbs used to be 100w and the fan is just 20-33w