Extract Fan Dilemma

[EFLImpudence]

the instructions must explicitly state suitability for installation in Zone 1.

701.55 does not say that.

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

 

[JohnW2]

..... John says that according to the good book, the instructions must explicitly state suitability for installation in Zone 1.

701.55 does not say that. .... "In zone 1, only the following fixed and permanently connected current-using equipment shall be installed, provided
it is suitable for installation in zone 1 according to the manufacturer’s instructions:"

I'm a bit lost - are you perhaps just quibbling about my having included the word "explicitly", which seems to be the only difference between what I wrote and what 701.55 says?

I personally cannot think of a way of interpreting that reg which doesn't meant that the MIs have to 'explicitly' say that the item is suitable for installation in Zone 1. 'Silence' in relation to the issue is surely not enough. As I wrote last night ...

..... Not saying that it is not suitable is not the same as saying that it IS suitable . The instructions presumably don't say that it is not suitable for Zone 0, either, but I would hope that you would not regard it as acceptable in Zone 0 (even if it were RCD protected and IPX4), would you?

Could you perhaps explain your viewpoint/interpretation? Thanks.

 

[Harry Bloomfield]

I have a small en-suite, around 1.7m x 1.6m.

Currently, there is a Vent Axia 4" fan in the wall opposite the shower enclosure.

It extracts 108 m³/h.

The en-suite gets steamy and the wall near the fan gets damp.

I've just been quite involved with my bathroom extract, recently. First let me say, we have zero moisture/mould issues at all, in the bathroom, despite using it for very regular baths and showers. Layout is bathroom on the lee side of the house (north/east corner), fan mounted on north facing wall, window faces east. Open the window, and if it's windy, air is sucked out. Bath, with electric shower above, is installed alongside the north wall, shower at the west end. The 4" fan is mounted high on the north wall, at the opposite end to the shower.

Originally, the bathroom had one of those silly window mounted vents installed, with a propeller. When I installed DG, I thought it best to add a proper electric fan, to ensure there was ventilation, to avoid any mould - but I only did half a job....

There had been a through the wall vent there before, except filled and plastered over on the inside, with a double brick vent on the outside. So I simply drilled through from the outside, to reopen the hole up, to fit a fan. Rather than fit a proper cowl to the outside, I made the poor decision to simply drill the holes in the air brick, much larger, and add a plastic pipe to line it through the cavity. It was a bad decision, because it caused lots of back pressure, making the fan much less effective. Besides which, I was struggling single-handed, and coping with an ill partner. Nonetheless, there was no problem with mould, so it remained like that for over a decade.

That fan, stopped working in the spring, not really a problem at that time, because the window would generally be open anyway, but a week or two back, I got a roundtuit to investigate the fault. An easy fix, just a failed resistor, in the supply to the controller. It is a PIR/timer/humidity triggered fan.

Having repaired that, I realised how poor the extract flow was, so I then set about (with Avril's help), knocking a hole through the air brick, and fitting a proper cowl, and sealed pipe on the outside.

Whether by design, or fortunate accident, I see that all the homes on this road, are laid out, despite five different designs of layout, including both sides of the road - with their bathrooms on the lee side of the house.

So I would suggest that the wind direction has quite a large part to play in keeping bathrooms free of moisture and mould.

 

[EFLImpudence]

I'm a bit lost - are you perhaps just quibbling about my having included the word "explicitly", which seems to be the only difference between what I wrote and what 701.55 says?

Well, that depends what exactly you mean by 'explicitly'.

Clearly you have confusion and doubt so not explicit - but I do not.

If you mean that it has to actually say the words 'item suitable for zone 1' then no, it does not say that.
However, it says it is suitable for bathrooms and is IPX4 which is what is required by 7671 for fitting in zone 1, so is actually 'explicit'.

I personally cannot think of a way of interpreting that reg which doesn't meant that the MIs have to 'explicitly' say that the item is suitable for installation in Zone 1. 'Silence' in relation to the issue is surely not enough. As I wrote last night ...

I disagree, listing the requirements necessary for zone 1 is not silence.
Would you require the manufacturer to state that the product is also suitable for zone 2?

Could you perhaps explain your viewpoint/interpretation? Thanks.

Done.

 

[securespark]

Well, I thought so, but John seems to disagree!

 

[JohnW2]

Well, that depends what exactly you mean by 'explicitly'. .... Clearly you have confusion and doubt so not explicit - but I do not.

As I suspected, basically just a quibble about words! If it helps (as as you suggest yourself below), just change my word "explicitly!" to "actually".

I have absolutely no 'confusion or doubt'. The simple fact is that if the MIs do not actually state that the item is 'suitable for installation in Zone 1" - which is what BS7671 requires.

If you mean that it has to actually say the words 'item suitable for zone 1' then no, it does not say that.

As above, I disagree. If you don't think it means that, what DO you think it means?

However, it says it is suitable for bathrooms and is IPX4 which is what is required by 7671 for fitting in zone 1, so is actually 'explicit'.

.... except that 701.55 actually says "... provided it is suitable for installation in zone 1 according to the manufacturer’s instructions:

The MIs saying that it is "suitable for bathrooms" obviously does not mean "suitable for all Zones of bathrooms", since IPX4 is not adequate for Zone 0. The manufacturer might feel, for whatever reason, that it was only suitable for Zone 2.

Would you require the manufacturer to state that the product is also suitable for zone 2?

If BS7671 actually stated that as a requirement, then yes (but it obviously doesn't)

This is all rather silly. As I've said, I personally would not care a jot about having contravened the literal wording of the regs in this case. However, in commenting on the fact that 10mm of plastic being <2.25m above FFL, secure seemed to be wanting "total 'strict compliance with the every word of BS7671!", which is why I have been pointing out to him what the words of BS7671 "actually say".

 

[JohnW2]

Well, I thought so, but John seems to disagree!

In terms of the actual wording of BS7671, I do disagree.

However, as I've said, I don't personally care a jot about any of this, any more than I would (again personally) regard something as being in Zone 1 because some plastic (but not electrical) bits of the item were <2.225m below FFL I would therefore (personally) regard it as being ';out of zones', in which case this entire discussion would be moot!

 

[EFLImpudence]

As I suspected, basically just a quibble about words! If it helps (as as you suggest yourself below), just change my word "explicitly!" to "actually".

It would be better because they do not actually say that but what they do say means that.

The simple fact is that if the MIs do not actually state that the item is 'suitable for installation in Zone 1" - which is what BS7671 requires.

The simple fact is that the MIs do state what BS7671 requires.

 

[JohnW2]

The simple fact is that the MIs do state what BS7671 requires.

In terms of what BS7671 actually says, there are three requirements for current-using equipment to be allowed in Zone 1.

1... It must be at least IPX4
2... It must be an item in the list [ (i) - (xi) ] in 701.55. That list includes "ventilation equipment".
3... it must be " suitable for installation in zone 1 according to the manufacturer’s instructions"

In the case we are discussing, requirements (1) and (2) are satisfied, but (3) is not.

 

[EFLImpudence]

In terms of what BS7671 actually says, there are three requirements for current-using equipment to be allowed in Zone 1.

1... It must be at least IPX4
2... It must be an item in the list [ (i) - (xi) ] in 701.55. That list includes "ventilation equipment".
3... it must be " suitable for installation in zone 1 according to the manufacturer’s instructions"

In the case we are discussing, requirements (1) and (2) are satisfied, but (3) is not.

It is not 1, 2, 3 like that, though, is it?

By stating in that the fan is IPX4 the manufacturer is saying it complies with (your)'1' from a previous regulation therefore meaning it is suitable for zone 1.

As I said before if the MIs said it was IPX3 then it would not be suitable for zone 1 or if it was IPX7 then it would be suitable for zone 0.

 

[JohnW2]

It is not 1, 2, 3 like that, though, is it? ... By stating in that the fan is IPX4 the manufacturer is saying it complies with (your)'1' from a previous regulation therefore meaning it is suitable for zone 1.

Ah, at last I understand why our view differ. However, if yous is correct, what BS7671 says doesn't really make sense (albeit, I suppose, 'not for the first time'!)

You appear to be saying that by saying that a fan (or anything else in that list) is at least IPX4, the manufacturer is automatically saying that they regard it as suitable for Zone 1. However, if that were the view of the authors of BS7671, there would have been no point/need for them to add "... provided it is suitable for installation in zone 1 according to the manufacturer’s instructions".

In other words, I have always presumed that BS7671 was considering the possibility that that, for whatever reason, a manufacturer might not consider their product suitable for Zone 1, even though it was at least IPX4 - since otherwise there would be no point in their "...provided that..." statement.

 

[JohnW2]

You appear to be saying that by saying that a fan (or anything else in that list) is at least IPX4, the manufacturer is automatically saying that they regard it as suitable for Zone 1. However, if that were the view of the authors of BS7671, there would have been no point/need for them to add "... provided it is suitable for installation in zone 1 according to the manufacturer’s instructions".
In other words, I have always presumed that BS7671 was considering the possibility that that, for whatever reason, a manufacturer might not consider their product suitable for Zone 1, even though it was at least IPX4 - since otherwise there would be no point in their "...provided that..." statement.

I was expecting that someone would challenge (or disagree with) what I said I had "always presumed", and was waiting for that before I expanded any further. However, since that has not happened, I will now mention the sort of situations in which I believe what I suggested could happen - i.e. that a manufacturer might feel that a product was not suitable for installation in Zone 1 of a bathroom, even though it was (and they said it was) at least IPX4 ....

.... there is nothing about a product being IPX4 that precludes very humid air/'steam' entering it, and such air is very likely to be present in Zone 1 (above a bath or shower). The manufacturer may therefore know, or suspect, that installation of the product in Zone 1 might result in impaired functionality and/or life expectancy - e.g. by condensing on PCBs and upsetting electronics and/or by causing corrosion of mechanical moving parts etc.

I therefore would say that it's quite possible that a manufacturer would not consider a product suitable for installation in Zone 1, even though it was IPX4, and therefore stick to my view that the regs really do mean what they say - i.e. that, to be acceptable in Zone 1, a product must not only be at least IPX4, but must also be 'actually said' by the MIs to be suitable for installation in Zone 1.

 

[EFLImpudence]

I did reply but do not know what has happened to my post.
I thought it unusual you would let me have the last word.

Anyway:

I was expecting that someone would challenge (or disagree with) what I said I had "always presumed", and was waiting for that before I expanded any further. However, since that has not happened, I will now mention the sort of situations in which I believe what I suggested could happen - i.e. that a manufacturer might feel that a product was not suitable for installation in Zone 1 of a bathroom, even though it was (and they said it was) at least IPX4 ....

Ok, but apart from the additional statement of suitability you think is required, IPX4 is all that BS7671 requires for installation in zone 1.

.... there is nothing about a product being IPX4 that precludes very humid air/'steam' entering it, and such air is very likely to be present in Zone 1 (above a bath or shower). The manufacturer may therefore know, or suspect, that installation of the product in Zone 1 might result in impaired functionality and/or life expectancy - e.g. by condensing on PCBs and upsetting electronics and/or by causing corrosion of mechanical moving parts etc.

Does BS7671 concern itself with and preclude the use of products because they might go rusty?

I therefore would say that it's quite possible that a manufacturer would not consider a product suitable for installation in Zone 1, even though it was IPX4, and therefore stick to my view that the regs really do mean what they say - i.e. that, to be acceptable in Zone 1, a product must not only be at least IPX4, but must also be 'actually said' by the MIs to be suitable for installation in Zone 1.

You say it is quite possible but is it the case for items that might need to be installed in such locations?

Do electric shower manufacturers actually state that their product is suitable for zone 1? I can't remember.

So - if they do not what does that mean for electric showers in your world?

 

[JohnW2]

I did reply but do not know what has happened to my post. ... I thought it unusual you would let me have the last word.

Fair enough. That seems to happen occasionally

Ok, but apart from the additional statement of suitability you think is required, IPX4 is all that BS7671 requires for installation in zone 1.

essentially yes, although (since you say "all that BS7671 requires"), in terms of current-suing equipment in general, there is a third requirement - namely that the type of item is included in the list in 701.55.

Does BS7671 concern itself with and preclude the use of products because they might go rusty?

Not directly (unless one counts hard-wired equipment as being part of the 'wiring system', in which case *** would apply). However, that's not the point - since, whatever the reason/thinking behind it, BS7671 does have a requirement for a "suitability for Zone 1" statement in the MIs.

Traditionally, BS7671 was all about 'safety' (not the interests of connected equipment), but the ('almost') 'requirement for SOPDs seems to have rather moved that goalpost.

You say it is quite possible but is it the case for items that might need to be installed in such locations?

One would hope not but, again, it does not alter the fact that BS7671 requires a 'suitability for Zone 1' statement in the MIs.

Do electric shower manufacturers actually state that their product is suitable for zone 1? I can't remember.

I can't remember, either - but ....

So - if they do not what does that mean for electric showers in your world?

It's not 'my world' - it's a question of what BS7671 'actually says' and 'requires'. However, yet again, if the MIs for showers do not include a 'suitability for Zone 1' statement then, strictly speaking, installing such an item in Zone 1 would not be compliant with BS7671.

I must repeat that I find this all very silly, and think that common sense should probably prevail. However, as I've said, I've only raised the issue because (by regarding something as being in Zone 1 despite no electrical parts being <2.25m above FFL), secure appeared to be wanting total and strict compliance with the 'actual wording' of BS7671.

 

[securespark]

You talk of humid air getting on to the PCB and the fan being deemed not suitable for Z1 by the mfr.

But would this humid air problem magically cease to be an issue if the fan was placed just inside Z2?