Can a householder install a fused fan isolator switch?

[humbert]

I have bought an extractor fan to go in my conservatory. It is a simple fan with a pull-cord and no run-on timer.

I want to wire it into my lighting circuit, but the installation manual insists on it having a 3a fused fan isolator switch.

I understand that a (not otherwise qualified) householder cannot legally install a fused spur off a socket circuit.

Do the regulations similarly prohibit me from installing a fused fan isolator of a lighting circuit?

Thanks.

 

[JohnW2]

Welcome to the forum!

I have bought an extractor fan to go in my conservatory. It is a simple fan with a pull-cord and no run-on timer. I want to wire it into my lighting circuit, but the installation manual insists on it having a 3a fused fan isolator switch.

They often do, but it doesn't really make much electrical sense,since the lighting circuit will presumably already have a 6A MCB (or, if old, 5A fuse). Many would be tempted to ignore that 'requirement'.

I understand that a (not otherwise qualified) householder cannot legally install a fused spur off a socket circuit.

That is not true.

Do the regulations similarly prohibit me from installing a fused fan isolator of a lighting circuit?

In view of my comment above, "similarly" is obviously not appropriate but, no, there is nothing in regulations to stop you doing that (except, possibly, if it were in a bathroom - which it isn't!).

Provided that you are comfortable doing it, just go ahead! The isolator is also not required, but some feel that it can be convenient to have itt for maintenance purposes.

Kind Regards, John

 

[opps]

I am not an electrician, but my understanding is that only new circuits need to be signed off. I might be wrong, but AFAIK you can run a spur because the circuit already exists. Naturally, it has to be done to spec but it is not notifiable (AFAIK)- if I am wrong, hopefully someone will correct me.

 

[JohnW2]

I am not an electrician, but my understanding is that only new circuits need to be signed off. I might be wrong, but AFAIK you can run a spur because the circuit already exists.

Indeed, even before the fairly dramatic relaxations in 2013 (in England, but not Wales) adding a spur to an existing circuit was one of the (relatively few) things that could be done without notification.

 

[EFLImpudence]

I am not an electrician, but my understanding is that only new circuits need to be signed off.

It depends what is meant by "signed off".

I might be wrong, but AFAIK you can run a spur

You can.

because the circuit already exists.

Not sure you can run a spur on a circuit that doesn't exist.

Naturally, it has to be done to spec but it is not notifiable (AFAIK)-

Of course.

 

[humbert]

Ah, thanks folks. I'm not sure where I got that idea from then.

Perhaps I mistakenly thought it counted as a "new circuit" when I looked into stuff a few years ago.

We have had a few new circuits put in, but we got a real electrician in to do the relevant part p notifiable bits.

 

[flameport]

Perhaps I mistakenly thought it counted as a "new circuit" when I looked into stuff a few years ago.

New circuits are those installed from an existing consumer unit.

The only items notifiable in England are
new circuits
replacement consumer units (not new ones where there was no consumer unit before)
and items within the zones in bathrooms (which is approximately nothing).

Installing an FCU from a lighting circuit is not notifiable and never was.

 

[JohnW2]

Installing an FCU from a lighting circuit is not notifiable and never was.

That's certainly how we all regard it, and almost certainly what was intended by those who wrote the notification rule, but as people have often pointed out, per BS7671 definitions an FCU does create a 'circuit' (hence a 'new circuit') which therefore could be argued to be notifiable.

However, as I wrote above, that would be a totally daft interpretation, since adding a spur to an existing circuit was one of the very few things that could be done without notification even before the extensive relaxations (in England) of the notification rules/requirements.