Extractor fan in bathroom, safety query

Blackbird89

Just wondering if anyone knows how extractor fans should be wired up?

I posted a thread previously stating it's wired up so when you turn on the shower the fan comes on automatically.

Anyway I've had an electrician out and he said it shouldn't be really, and he asked my partner where the fuse box was and said the shower and extractor fan are working off a 40 amp fuse. My partner asked is that good or bad? Because he's no electrician, and the electrician fella said "well it's not good is it" anyway the electrician has allegedly emailed the agency we rent from telling them it's safe but when they were here (there were 2 of them) one told the other to pull the shower cord to check if the extractor was indeed connected to the shower so he did and the fella that asked him to do so said bloody hell yeah it is TURN IT OFF..

So is it safe or not? We were told it wasn't good and the electricians reaction made us think it's not safe, but they've told the agency it is..

I mean if it is safe and not a hazard (we've lived here 15 months already with no issues) then they can just replace the fan as far as where concerned as it's easiest thing to do..

Other option the electrician said is to disconnect it from the showers power feed put it on it's own circuit but they'd have to take all insulation up in the loft etc.. Not a problem to us really but they didn't sound like they wanted to do it.

Another thing the electrician said to my partner was when the shower is on it will always have 40amps running through it and we don't want that, so I'm curious as to why not? It's caused no issues in the past but obviously we wouldn't want to be put in a dangerous situation if it can be avoided.

Any thoughts?

And sorry for the long message, just getting point across that where not that fussed if they just want to replace the fan, but if there is any risk to us then obviously they should put it on it's own circuit.

Thanks.

fto

Yes it is dangerous.
The fan should not be on the same circuit has the Shower.
Get them change it.

malcolmffc

"Another thing the electrician said to my partner was when the shower is on it will always have 40amps running through it and we don't want that, so I'm curious as to why not?"

Because that is an absolutely lethal level of current if it ever comes into contact with you. Standard procedure is to wire the extractor fan into the lighting circuit for the bathroom, which will have less than a tenth of that amperage.

cutandshut

malcolmffc wrote: »

"Another thing the electrician said to my partner was when the shower is on it will always have 40amps running through it and we don't want that, so I'm curious as to why not?"

Because that is an absolutely lethal level of current if it ever comes into contact with you. Standard procedure is to wire the extractor fan into the lighting circuit for the bathroom, which will have less than a tenth of that amperage.

That is absolute nonsense! You obviously know nothing about electricity.

princeofpounds

Have been googling around and it's clearly wrong as per building control and electricity regulations.

I don't know about it zapping you, but I can think of one obvious problem; the fuse is totally wrong for the fan. If the fan has a problem and ends up with too much current running through it, a fuse is meant to break when too much current runs through for the device.

This fuse clearly isn't going to do that, so the fan wiring could start to burn I suppose.

It's not likely to go wrong as it's not a complicated device, but it's not great.

junglejim2

Fan being wired from the shower supply is a a fire hazard, it needs to be wired correctly asap.

A 9kw shower will draw around 40 amps, this is normal and nothing to worry about. If it didn't draw 40 amps it would be a cold shower;)

chappers

Well basically there is a risk, it is a potential fire hazard.
Fans are usually wired into the lighting circuit so they come on with the light and are therefore protected by the correct fuse/breaker.

Davesnave

The shower fan may have been fitted this way to prevent tenants doing what they often do, which is use a shaver light, if fitted, and thus circumvent the use of the fan on cold mornings, exactly when condensation is worst!

gollum007

junglejim2 wrote: »

Fan being wired from the shower supply is a a fire hazard, it needs to be wired correctly asap.

A 9kw shower will draw around 40 amps, this is normal and nothing to worry about. If it didn't draw 40 amps it would be a cold shower;)

That's not strictly true.
If the fan is wired directly from the shower supply without downfusing appropriately, *then* it's a potential fire hazard.

On the other hand, if a 6mm2 wire is taken from the shower switch to a FCU with a suitable (3a) fuse in it, and from there to the fan, then whilst not ideal, then there's nothing really wrong with that.

-Gollum

chappers

That is correct assuming that the fused spur is also rated at 40amps

ValHaller

It can be done safely as described, with a low voltage fan and transformer wired off a suitably fused spur from the feed to the shower.

Whether it actually is is another matter