PIV unit in a 27sqm flat overkill?

ThisIsWeird

hang3r said:

ThisIsWeird said:

Note, despite its price and all of its features, it's still an axial fan. And, as we've established earlier, those by design don't work with bent/long ducting like mine.

I'm not sure that has been established at all?
And all these fans are 'axial', including yours.
But, I am not saying that the Vent-Axia is the best, as I just don't know. All I'm suggesting is, if you are going for a £100+ model, then it should be considered, as it's super quiet, very effective, and has a lot of control.
Bottom line in extractor-fan effectiveness, tho', is its flow rate, so compare these. And how sensitive any auto humidistat is. 
And quiet is also good. :-)

If you look at one of the earlier reply from @ic, or a quick google search will confirm from different sources that axial fans are best for straight runs like directly through a wall to outside, or at most very short ducting with little in the way of bends. Compared to centrifugal ones that are able to handle long ducting.

According to the manufacturer's official website it is a centrifugal fan not an axial one. I don't see why they would mislead over such a basic thing that can be easily and quickly confirmed by anyone who bought it.

From simple through the wall installations to complex ducting/bend systems the EnviroVent Filterless Extract Fan will deliver the performance to meet building regulations and beyond. The centrifugal impeller with its unique helical power expansion chamber enables the unit to achieve power with efficiency and quietness in the most compact unit ever.

https://www.envirovent.com/products/extractor-fans/filterless-extract-fan/

My apologies. There was no reference to 'centrifugal' in the initial link, and it looked like an axial fan. :-)
I don't know which one is best, but I'd choose an extractor mainly on flow rate and noise level. 
The Vent-Axia is ~36m3 at 19db tickover, and 100+ (I forget figure) at max, and still only 44db.

hang3r

ThisIsWeird said:

My apologies. There was no reference to 'centrifugal' in the initial link, and it looked like an axial fan. :-)
I don't know which one is best, but I'd choose an extractor mainly on flow rate and noise level. 
The Vent-Axia is ~36m3 at 19db tickover, and 100+ (I forget figure) at max, and still only 44db.

No worries. If the manufacturer's specs are to be believed, the one I linked earlier does 50m3 at 13dba and 147m3 at 35dba.