Recommendations for a Zone 1, extractor fan.

[DoogyDawg]

As it says really.
The impossible I know, but thought I would ask any way.
I need to get a Zone 1 extractor fan. (wall mount)
100mm
4" blades.
Backdraft feature, built in, not anything you have to stick in the pipe.
High (as possible air intake 74?? or what ever it is)
Fan grill showing, not the kind with a decorative plate on the front, as it gives a ninety-degree angle to suck the air in.

We have a solid pipe through the wall, new build, of 20 years ago.
We had a new en-suite, and they put a cheap fan in it, and we are getting condensation runs/stains on the paintwork, and you can here the thing in the livivng room from upstairs.
So, what have you got? I have looked at so many, and the numbers are daunting trying to compare them to each other.
Our budget is up to £100. My installer said to look at Expelair or Vent axia.
Cheers for any replies.

 

[Murdochcat]

Whilst there are some fans that are ok for zone 1 my recommendation is 12v.

As for the existing fan do you have sufficient air flow under the door? 6 - 10mm is necessary

 

[securespark]

This sounds silly, but what recommendations did he make?

 

[securespark]

As for the existing fan do you have sufficient air flow under the door? 6 - 10mm is necessary

This is a really good point.

An adequate gap is needed under the door so the fan can suck sufficient air from outside the room to replace the air it extracts.

We had a fan fitted in our en-suite as part of a load of renovations. I argued with Mrs S It needed the door truncating. She didn't want that, complaining it would be "chilly". The company made no mention of needing a gap. It failed prematurely. I argued again with Mrs S that it needed adequate gappage.

Anyhow, the company replaced it. Again with no mention of a gap needed under the door.

And that failed too.

So I replaced it with a different brand. But not until a goodly chunk of door was sliced off the bottom.

So far, so good.

PS

There is a formula somewhere to calculate how big the gap should be, depending on how wide the door is and how big the fan is.

 

[JohnW2]

As for the existing fan do you have sufficient air flow under the door? 6 - 10mm is necessary

This is a really good point. .... An adequate gap is needed under the door so the fan can suck sufficient air from outside the room to replace the air it extracts.
There is a formula somewhere to calculate how big the gap should be, depending on how wide the door is and how big the fan is.

I'm sure that there will be a 'formula' somewhere, but one can have a stab at this without it.

Intuition/common sense would suggest that the area of the gap under the door should be least as great as the area of the output duct of the fan - probably a bit more, since the extracted ait is being pumped out at a pressure a little above atmospheric. That would mean that, if the fan had a 100mm diameter round output duct, the gap under a 760mm wide door should be at least about 10.3 mm. Maybe that's how "the formula" works?

Edit: In passing, you say that the two fans you tried before chopping a bit off the door both "failed". Do you mean that the fans stopped working? If so, I doubt very much that you could blame those failures on the lack of a gap under the door.

 

[securespark]

No, they carried on working, but got extremely noisy and clattery.

Both the same brand and both went exactly the same way.

Xpelair Simply Silent DX150R 150mm Round Extractor Fan Timer | Toolstation https://share.google/DOMcDgnoi2lyWnVy3

 

[JohnW2]

No, they carried on working, but got extremely noisy and clattery. Both the same brand and both went exactly the same way.

Interesting. Whilst lack of adequate ventilation (gap under door) will presumably very slightly increase the 'stress', hence 'wear', on the fan, I do seriously doubt that would be enough to result in significantly premature failure.

 

[JohnD]

"got extremely noisy and clattery"


I find the ball-bearing fans by Envirovent/Soler & Palau much better.

 

[JohnD]

I need to get a Zone 1 extractor fan. (wall mount)
100mm
4" blades.
Backdraft feature, built in, not anything you have to stick in the pipe.
High (as possible air intake 74?? or what ever it is)
Fan grill showing, not the kind with a decorative plate on the front, as it gives a ninety-degree angle to suck the air in.

Soler & Palau Silent 100. Also sold under Envirovent brand.

IP45 rated
Airflow; 95 m3/hr
Power Consumption: 8 watts Max
Very Low Noise: 26.5 dB (A)
Face Plate: 158mm Sq x 24mm deep
Backdraft shutter
Ball bearings

https://www.tlc-direct.co.uk/tcl/search?query=silent%20100&sort_order=&category_id=&sub_category_id=&manufacturer_ids=

(I have no axe to grind)