IPX4 fan suitable for Zone 1?

[Jeff Layman]

I have bought an Auro eco 100MST fan for bathroom ventilation:

There was already a suitable 100mm passive vent duct fitted, but it was only 2.15 metres above the bath, in Zone 1. The electrician I asked to connect it up said that it really had to be in Zone 2 as it was not a SELV fan. I told him we had a new consumer unit fitted only a couple of years ago, with a 30mA breaker on it, but he was still unhappy about fitting the fan and certifying the installation (it has not yet been installed).

I have since tried to check what Part P requires, and can see why he was more than a bit doubtful. On the internet there seem to be many conflicting views about the requirements, and some comments seem to contradict themselves!

So what do those here think? Can a 230v IPX4 fan connected to a 30mA breaker be installed in Zone 1 in a bathroom and still comply with Part P?

[ARW]

Only if the manufacturer says so.

see note 3

[Chris French]

In message , Jeff Layman writes

Do you mean above bath or above floor? According to the zone diagram in the onsite guide zone 1 finishes 2.25 m above the floor.

Zone 1 IPX4 rated (unless water jets when IPX5)

mains voltage - various fixed permanently connected equipment listed - including ventilation equipment.

So, yes it is (want copy of the relevant page? :-) )

RCD protection is irrelevant in this context. Though it does mean the bathroom doesn't need supplementary bonding.

[Tim Watts]

I solved my issue with this by using an inline fan in the floorspace above the ground floor bathroom - ducting to the bathroom and to the outside.

I also believe there are 12V SELV fans available too.

[Jeff Layman]

Thanks for that link. Note 3 seems pretty definitive.

But I think this is where some interpretation problems occur. Firstly, is this a NICEIC interpretation, or does BS7671 specifically state what is in Note3 (I tried to see a copy in my local library but they didn't have BS7671)? Does that mean the manufacturer has to specifically state that the equipment is suitable for Zone1, and "suitable for use in a bathroom" isn't sufficient? I could not find anywhere in the documentation with the fan or on their website that Airflow state specifically that the particular model I have purchased is suitable for use in Zone 1. I will email them to see if they will confirm it - or not as the case may be!

[Jeff Layman]

I meant 2.15 metres from the floor. Sorry for the ambiguity.

Is your reference to the relevant page the same as the link in ARW's reply? If so, please see my reply to him.

[Andrew Gabriel]

In a previous house for one of my relatives, the new shower cubicle already had a 3.5" duct straight through a very thick wall (originally a basement retaining wall but outside had been cleared of soil at some point to make garden access from the basement). The duct had been a boiler flue, and given it was there, I was going to use it rather than make another hole. (ISTR the wall was 2 bricks thick, i.e. 18"+.)

I built an extractor to go on the outside of the wall, so it was not accessible from the shower cubicle at all. Of course, it had to be weather proof, but that wasn't hard. It somewhat surprised me that there was no such product commercially available at the time (nor since, AFAIK). On the inside, a simple circular grille was fitted to hide the view of the hole.

[Chris French]

No it is the IEE On-Site Guide, basically a sort of quick reference guide to the regs

(mine is a couple of editions ago, so doesn't have amendments, but AFAIK, nothing changed in this respect)

The relevant page is here:

It mentions nothing about manufacturers instructions.

[ARW]

"Reg 701.55 Current-using equipment

In zone 1, only the fixed and permanently connected current-using equipment shall be installed, provided it is suitable for installation in zone 1 according to the manufacturers instructions".

A yes and a yes.

gives no definite answer - but it says a 3A fuse must be fitted.

I have a feeling that the manufacturer will say that the fan must not be accessible to a person using the bath.

Personally I would have fitted it as it is IPX4. Any reason why you cannot DIY it and sod Prat P?

[Jeff Layman]

Thanks for the clear reply, Adam.

If they reply at all...

I could install it - there's no technical difficulty. The reason I wouldn't isn't because of elf'n'safety concerns. It's because in case of any damage to the house (whether related to the fan or not), the bloody insurance company would no doubt quote some obscure paragraph and invalidate the whole insurance. Actually, where the electrician would move it to is more convenient for operation - less likelihood of the PIR getting false triggers from an open bathroom door.

I'll get the electrician to do it and certify it. It would cost me quite a bit to buy a 100 mm diamond core drill (which I would probably never use again) for the ducting, anyway.

[charles]

I'd expect your electrician to hire it.

[Jeff Layman]

Thanks. Maybe the manufacturer's instructions are mentioned in one of the amendments.

[Jeff Layman]

He has one. It was me I was referring to who needs the diamond core drill if I did the work myself.

[PeterC]

The outlet for my fan is high up on the SW wall, so I fitted a cowl to keep off direct wind and rain - might be OK for an exterior fan:

[RobertL]

If zone 1 extends up to 2.25m then can you perhaps recess the fan into the ceiling by 100mm?

Robert

[RobertL]

They do exist: our kitchen extractor fan is mounted on the outside of the house and is built for the purpose (has a stainless steel enclosure). We did that to reduce the noise in the kitchen - which it did BTW.

[Andrew Gabriel]

I found an old picture of the one I did - similar idea

[ARW]

If I was doing the electrical work and certification I would be delighted to lend you my core drill and let you drill the hole for me and I would knock that part of my labour off the bill. Core drilling is a horrible job.

BTW Please let us know what the manufacturer says (if anything) about installing the fan in zone 1. TIA

[Jeff Layman]

Thanks for the offer, but that's only half of it. This place had cavity wall insulation done with polystyrene beads. At the time it was done, they either used beads without adhesive, or it's degraded and no longer working. We had some crappy patio doors replaced last week, and at least half a cubic metre of those &/"%*\{ beads poured out when the old doors were removed. They blew all over the garden as it was very windy and as it's been p*ssing down ever since, trying to vacuum them up is a waste of time. So when that core drill penetrates the cavity, and it's pulled back to insert the duct...

Will do.

[fred]

In article , Jeff Layman writes

Sound like you're havin fun :-/

Consider drilling half a dozen 8mm holes around the planned core site and squirting in some dilute pva to set things together. If you have some builders' foam spare then that would put things beyond risk.