I'd like to wire the shower room extractor fan from the shower pull-switch so that it goes on with the shower and not the light. I found some info where one person said it's a no-no under current wiring regs but could be done via a contactor, and another says it can be done without a contactor as long as it goes via a fused spur from the shower switch.

Any electricians here can tell me which is the legal way to do it as I'd like to do it through a fused spur from the shower pull switch for simplicity..

Why do you use the shower isolator in normal use?

On 27/10/2020 14:57, me wrote:

I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity..

You can do it with a fused spur from the shower isolator switch it you
want. You should label it at the consumer unit to avoid surprises for
later maintainers. Also since you would be removing all power from the
fan when you turn the switch off, you would lose any ability to have a
an automatically timed run on after the shower.

If you wanted to power and trigger the fan from the lighting circuit,
but also trigger it from the shower circuit, then you get into the
realms of needing contactors/relays etc to keep the circuits
electrically isolated from each other.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

John Rumm Wrote in message:
On 27/10/2020 14:57, me wrote:

I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity..

You can do it with a fused spur from the shower isolator switch it you
want. You should label it at the consumer unit to avoid surprises for
later maintainers. Also since you would be removing all power from the
fan when you turn the switch off, you would lose any ability to have a
an automatically timed run on after the shower.


Could he wire it from the supply side of the shower switch & avoid
that?

--
Jimk


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

Jimk Wrote in message:
John Rumm Wrote in message:
On 27/10/2020 14:57, me wrote:

I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity..

You can do it with a fused spur from the shower isolator switch it you
want. You should label it at the consumer unit to avoid surprises for
later maintainers. Also since you would be removing all power from the
fan when you turn the switch off, you would lose any ability to have a
an automatically timed run on after the shower.


Could he wire it from the supply side of the shower switch & avoid
that?


The permanent live for overrun I mean...
--
Jimk


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

On 27/10/2020 17:12, Jimk wrote:
Jimk Wrote in message:
John Rumm Wrote in message:
On 27/10/2020 14:57, me wrote:

I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity..

You can do it with a fused spur from the shower isolator switch it you
want. You should label it at the consumer unit to avoid surprises for
later maintainers. Also since you would be removing all power from the
fan when you turn the switch off, you would lose any ability to have a
an automatically timed run on after the shower.


Could he wire it from the supply side of the shower switch & avoid
that?


The permanent live for overrun I mean...



or even wire the fan into the shower itself, so picking up the permanent
live before the controls and the switched live after the controls?

Thus removing the risk of confusion if wired into the the shower
isolation switch?

S.

@John Rumm, not sure I understand what you're saying. What I intended was to run some three core and earth from the shower pull switch so that I'd have a permanent live and neutral and a switched live all going to the fan via a fused fan isolating switch. So the fan will still run on when the shower pull switch is turned off after using the shower. None of that would go near the consumer unit of course. Does that sound ok?

No Name Wrote in message:
On 27/10/2020 17:12, Jimk wrote:
Jimk Wrote in message:
John Rumm Wrote in message:
On 27/10/2020 14:57, me wrote:

I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity..

You can do it with a fused spur from the shower isolator switch it you
want. You should label it at the consumer unit to avoid surprises for
later maintainers. Also since you would be removing all power from the
fan when you turn the switch off, you would lose any ability to have a
an automatically timed run on after the shower.


Could he wire it from the supply side of the shower switch & avoid
that?


The permanent live for overrun I mean...



or even wire the fan into the shower itself, so picking up the permanent
live before the controls and the switched live after the controls?

Thus removing the risk of confusion if wired into the the shower
isolation switch?

S.


What "controls" are you talking about?
--
Jimk


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

On 27/10/2020 17:12, Jimk wrote:
Jimk Wrote in message:
John Rumm Wrote in message:
On 27/10/2020 14:57, me wrote:

I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity..

You can do it with a fused spur from the shower isolator switch it you
want. You should label it at the consumer unit to avoid surprises for
later maintainers. Also since you would be removing all power from the
fan when you turn the switch off, you would lose any ability to have a
an automatically timed run on after the shower.


Could he wire it from the supply side of the shower switch & avoid
that?


The permanent live for overrun I mean...

You could although you would need to fuse that as well, since many fan
manufacturers spec a 3A supply fuse.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

John Rumm Wrote in message:
On 27/10/2020 17:12, Jimk wrote:
Jimk Wrote in message:
John Rumm Wrote in message:
On 27/10/2020 14:57, me wrote:

I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity..

You can do it with a fused spur from the shower isolator switch it you
want. You should label it at the consumer unit to avoid surprises for
later maintainers. Also since you would be removing all power from the
fan when you turn the switch off, you would lose any ability to have a
an automatically timed run on after the shower.


Could he wire it from the supply side of the shower switch & avoid
that?


The permanent live for overrun I mean...

You could although you would need to fuse that as well, since many fan
manufacturers spec a 3A supply fuse.


Presumably it'll need fusing wherever it's fed from then?

What's the neatest way to do that?
--
Jimk


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

Many moons ago, I recall an extractor which had rechargeable batteries in a
little well quite big box which also had a mains to low voltage psu in it..
The idea was that the batteries kept the fan on for a few minutes after the
mains went off. I remember at the time thinking, this looks like a bit of a
problem when the batteries start to not hold a charge!

Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"John Rumm" wrote in message
o.uk...
On 27/10/2020 14:57, me wrote:

I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity..

You can do it with a fused spur from the shower isolator switch it you
want. You should label it at the consumer unit to avoid surprises for
later maintainers. Also since you would be removing all power from the fan
when you turn the switch off, you would lose any ability to have a an
automatically timed run on after the shower.

If you wanted to power and trigger the fan from the lighting circuit, but
also trigger it from the shower circuit, then you get into the realms of
needing contactors/relays etc to keep the circuits electrically isolated
from each other.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 27/10/2020 14:57:12, me wrote:
I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity.

Most people would opt for a fan with a humidistat.

Fredxx Wrote in message:
On 27/10/2020 14:57:12, me wrote:
I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity.

Most people would opt for a fan with a humidistat.




I wouldnt they fail all the time...
--
Jimk


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

On 27/10/2020 14:57:12, me wrote:
I'd like to wire the shower room extractor fan from the shower
pull-switch so that it goes on with the shower and not the light. I
found some info where one person said it's a no-no under current
wiring regs but could be done via a contactor, and another says it
can be done without a contactor as long as it goes via a fused spur
from the shower switch.

Any electricians here can tell me which is the legal way to do it as
I'd like to do it through a fused spur from the shower pull switch
for simplicity.

Have you considered of a PIR sensor to detect someone in the bathroom?
Might be additionally useful for when someone does a smelly No 2.