SOLVED Old extractor fan has TNL; new only has NL

[opps]

I am really confused.

The old fan never worked from the moment that the OP moved in but the new one works like the old one did...

And although there is only a switched live, the OP says that they can turn the fan on when the light is off?

 

[JohnW2]

Every timer fan I've ever installed has needed the permanent live connected to the timer which then keeps the fan running after the switched live is removed ...

Nor just "when the switched live is removed". Even when the switched live is there (.e. the light is on) it is the permanent live which powers the fan. The switched live merely ';triggers' the electronics to connect the permanent live to the fan.

but switches it off after the set time. That is what I was understanding the Op. to mean in his suggestion B

If, as has always been the case with every timer fan I've seen, 'T' ('Trigger') designated the switched live, then the OP's "suggestion B" would result in the 'other L' (the permanent live) being connected to the new non-timer fan's (only) L terminal - in which case, as I wrote, the fan would operate continuously, regardless of whether or not the light was on.

Kind Regards, John

 

[DOIDIY]

Make up your mind.


That doesn't make sense.


That is probably because you had the L and LT wires the wrong way round otherwise your new one would not work properly.

All’s well that ends well - I have a working new fan working the same as the old one that broke! I don’t understand much about electrics but followed the advice given and got what I needed- thanks again to those that offered advice!

 

[DOIDIY]

I am really confused.

The old fan never worked from the moment that the OP moved in but the new one works like the old one did...

And although there is only a switched live, the OP says that they can turn the fan on when the light is off?

The old fan didn’t have a timer that worked. Otherwise it functioned fine ie. turned on and off.

The new one does that now and yes I can use the isolator switch to have the fan on whilst the light is off - that’s the same as another fan I have that’s been fitted by electricians which I assumed was standard?

 

[RandomGrinch]

The old fan didn’t have a timer that worked. Otherwise it functioned fine ie. turned on and off

 

[EFLImpudence]

yes I can use the isolator switch to have the fan on whilst the light is off -

That's not an isolator.

 

[JohnW2]

The old fan didn’t have a timer that worked. Otherwise it functioned fine ie. turned on and off.

Ah - in that case, as has been suggested by RandomGrinch, the old fan was probably wired incorrectly, with 'T' and 'L' swapped around from how it should have been.

That would explain everything, including your success in getting it working with your 'option B'.

Kind Regards, John

 

[ebee]

That's not an isolator.

Correct, it sounds like improper use or confusion with terminology and the original terminology has got some of us confused.
After reading the whole thread to date I think you actually meant that the timer fan did not work as a timer fan but did work as a normal untimed fan, now you have changed it for a normal untimed fan then again it works as a normal untimed fan , so no loss but no gain also.
I think by "isolator" you actually did mean that you now have a switch for the fan independent of the switch for the light so you can switch one or the other or both on or of.

PS looks like the initial fan was wired improperly but worked so the new fan now works by the same method.
By improperly I am referring to improper use of the terminals .
The terms L, N and T can be confusing unless the manufacturer has made it clear what the function of each terminal actually is.

If you were to get a new working timer function fan it would work (like a normal untimed fan) with simple N connected to Neutral and a switched L connected to both L and T terminals (Say a short linkwire connecting the both together_).

If you still not sure what I mean then I will draw it to , hopefully, make it easier.

 

[JohnW2]

I think by "isolator" you actually did mean that you now have a switch for the fan independent of the switch for the light so you can switch one or the other or both on or of.

I thought that what the OP had now done (his 'option B') was to connect the switched live (previous misused as a permanent one (used as 'L', not 'T') to the (only) L terminal f the new (no-timer) fan.

If that is the case, if the isolator is closed, the fan will come on/off with the light, and, if the light is on, the fan can be turned off with the isolator, but it would NOT be possible to turn on the fan if the light were off.

Kind Regards, John

 

[ebee]

Oh yes, yet another interpretation I had not considered.

 

[EFLImpudence]

The terms L, N and T can be confusing unless the manufacturer has made it clear what the function of each terminal actually is.

What else do you think L, N & T can mean in such a context?

 

[JohnW2]

What else do you think L, N & T can mean in such a context?

Indeed. As I've been saying all along, I think it pretty obvious what L, N & T mean, as has been the case with every timer fan I can recall having seen.

 

[DOIDIY]

Correct, it sounds like improper use or confusion with terminology and the original terminology has got some of us confused.
After reading the whole thread to date I think you actually meant that the timer fan did not work as a timer fan but did work as a normal untimed fan, now you have changed it for a normal untimed fan then again it works as a normal untimed fan , so no loss but no gain also.
I think by "isolator" you actually did mean that you now have a switch for the fan independent of the switch for the light so you can switch one or the other or both on or of.

PS looks like the initial fan was wired improperly but worked so the new fan now works by the same method.
By improperly I am referring to improper use of the terminals .
The terms L, N and T can be confusing unless the manufacturer has made it clear what the function of each terminal actually is.

If you were to get a new working timer function fan it would work (like a normal untimed fan) with simple N connected to Neutral and a switched L connected to both L and T terminals (Say a short linkwire connecting the both together_).

If you still not sure what I mean then I will draw it to , hopefully, make it easier.

You’re spot on here! Again - I got what I came for lol and one happy man as I’ve got my fan working and that’s great for a non sparky like me. Timer would be great but saving money is better

 

[JohnW2]

You’re spot on here! Again - I got what I came for lol and one happy man as I’ve got my fan working and that’s great for a non sparky like me. Timer would be great but saving money is better

Like others, I'm still confused, which presumably means that I/we have misunderstood something.

As eBee wrote, your recent posts seem to have suggested that the old ('broken') fan was actually still working, but not as a timer fan (which we believe was due to it having been wired incorrectly).

You have now successfully replaced it with a new, no-timer fan,which is working satisfactorily, but obviously not as a timer fan (which it isn't!).

If that were all true, you would (as eBee wrote) not have achieved any change, and arguable will have 'wasted' what you paid for the new fan.

What are we misunderstanding?

Kind Regards, John

 

[opps]

I am still confused.

The old fan worked but without the timer over-run. The OP replaced a fan that runs, with a fan that runs...

And I can not work out how a fan with a switched live from the light can work independently via the isolating switch. For that to be the case, it would possibly imply that the isolating switch has been wired such that it turns the switched live into a perm live.

To the OP- can you confirm that the fan turns on when the light is turned on. Assuming, as per your other posts, it does run, what happens if you flick the isolating switch?