Centrifugal Bathroom extractor - build quality?

[dishman]

I am replacing an old bathroom extractor. It is more than 35 years old.

It vents into a shared riser duct and the run is probably 1.5m or so from the external vent on the building exterior.

So a centrifugal extractor is most suited for this scenario.

Ideally I want one with a timer function for over-run, but nothing much else in terms of fancy gadgets that can break (pir or humidistat).

Are there any specific brands that people have come across that seem to provide better quality components/construction? Manrose? Vent Axia?

The bathroom involved is windowless and small, so a good/reliable extractor is pretty important.

 

[flameport]

https://www.tlc-direct.co.uk/Products/AD01.html

 

[dishman]

Oooh, that looks like a nice solid/simple design.

 

[JohnD]

But very much noisier than modern designs.

Does it have to go straight through the wall, or is there a duct you can get at?

 

[dishman]

I did notice the db figure. I was pondering how loud 54db was.

No, it's a shared "dry riser" type affair. This one is top floor, and the current extractor mounts onto the wall. and vents into the vertical "shared" riser.

The current extractor looks very similar to this one actually. It box mounts onto the wall.

It's a shame to get rid of it as the build quality does seem to be designed to last. But it is 40 years old, and it may be seems to be struggling to vent enough.

 

[JohnD]

54dbA is very loud.

I recently got rid of a Manrose rated at 42db which was annoyingly noisy. The replacement is 26.5db with a ball-bearing motor, and you wouldn't know it was on unless you looked at the blades (when you turn it on and off you notice ambient sound changes, unless there is a tap running, or a plughole draining, or the window is open, or wind is blowing through the trees outside). But it is only 95 cu.m/hr which might not be enough for you. https://www.tlc-direct.co.uk/Products/SLS100CRZ.html

Here's a quieter and more powerful one, if you have room for it.
https://www.tlc-direct.co.uk/Products/SLTDK160T.html
They make a large range.

I only had a 4" duct. If you have a 5" or 6" there is more choice of powerful and quiet fans.

Is your old one clogged with dust?

 

[dishman]

Not sure about how clean.

I've just been encouraged to replace it.

The duct is not accessible. But it is a void that runs vertically through all the flats. So this has to mount on the wall of the duct, and just vent into it.Hence it needs a centrifugal wall mount. An inline or an axial is no good do to the longish duct run.

I may have to look for some quieter options then. I just want to avoid cheap crap that will only last a few years.

 

[JohnD]

What size duct will it fit?

 

[dishman]

This probably explains it better than I am. The riser vent is on the other side of the wall it is attached to.

So with the fan removed....

As you can see, there is just a cut out in the wall panel and it vents into the shared "riser vent".

That flap is the back flow flap.

I assume any modern wall mounted extractor will probably need a new cut-out and slot into it.....something like that I guess?

 

[JohnD]

Looks surprisingly clean

I reckon you could fit something quite big

What are the dimensions of the hole in the wall?

It might benefit from a fire-stopping shutter.

 

[dishman]

Ahh, this photo is from a few years ago. But, I did check it about a year ago and it was still pretty clean actually.

Yes, any sizeable wall mount would fit, but the bathroom is tiny. maybe 1.5m by 2.5m and 2m high.

I would not want anything too big. Just something that is quiet and (for modern stuff) reliable. This thing is actually pretty damn quiet.

 

[dishman]

Any thoughts on Vent Axia?

https://www.extractorfanworld.co.uk...entrifugal-extractor-fan-with-timer-137-p.asp

or Xpelair

https://www.xpelair.co.uk/product/premier-cf20-fan-220-240v-50hz

There is a manrose, which is pretty cheap.
https://www.extractorfanworld.co.uk/manrose-cf200t-centrifugal-extractor-fan-with-timer-268-p.asp

It's been suggested that the existing fan, although clean, may not be up to the job any more and the motor (although not showing any signs of breaking/bad noises etc) will not be doing as good a job as it was from new).

I just don't want a modern fan with crappy build quality where the bearings will go after a few years.

 

[dishman]

I think I may go with this one, unless anyone know of an issues with the brand/model.

Seems quiet, and the L/min seem pretty good.

https://www.extractorfanworld.co.uk...ntrifugal-extractor-fan-with-timer-4961-p.asp

I also wanted to check. The current fan is supplied by a switched live only. So it can only go on with the light.

This has an overrun function, I understand this will not function. I assume this can be installed to operate just with switched function for now?

 

[flameport]

It's been suggested that the existing fan, although clean, may not be up to the job any more and the motor (although not showing any signs of breaking/bad noises etc) will not be doing as good a job as it was from new).

Motors generally either work properly or not at all.

Is there actually anything wrong with the existing fan? Does it even need replacing?