can manrose MF100T inline fan be installed over xpelair C4TSR axial fan

[coolio]

Hi i am looking for some advise regarding a bathroom extractor fan currently fitted to my new bathroom refurbishment.

Problem i have is a reputable bathroom company has recently refurbished my bathroom and fitted a Xpelair C4TSR fan which does not extract enough moisture out of the bathroom, the fan is currently connected to existing soil pipe in the loft which is vertical through the roof. this soil pipe was reduced in the bathroom and a dergo valve fitted.

The company agree it is not correct and want to fit a manrose inline fan in the loft and connect ducting directly to the still operational xpelair fan and vent out of the vertical stack pipe, resulting in 2 x fans working on one ducting.
can anyone advise if this will work, and not cause any damage to either fan and is it within the regulations.
My other questions are....
1. Does it need a condensation trap fitted to the vertical stack pipe in the loft which goes outside through the roof tilles.
2. Does all ducting need to be insulated.
3. it is installed into the ceiling in a corner at the furthest point away from shower next to a window, is this correct or should it be fitted closer to the shower and further away from the window.

Hopefully this all makes sense and someone can point me in the right direction.

Looking forward to hearing your professional opinions

Cheers
Coolio

 

[littlespark]

First of all, I would say the position is wrong. If the window is open, then the fan will simply draw air in through the window, and very little of the shower moisture will be affected.

how high is the vertical run of duct? Short length, it should be ok.

you also mention a durgo valve? Is that not for letting air IN the top of a soil pipe? In which case the fan is pushing against a closed valve. (Is there another type?)

 

[snowhead]

So currenty the Expelair uses the now redundant section of Vent pipe in the loft that was cut off when the vent was cut down into the bathroom?

I assume this vent exits the roof vertically, as all Soil vents should, if so that means unless it had a suitable vented cap on it there is a risk of rain getting into the vent and back through the fan into the bathroom.

It's a disaster.

As Littlespark above, the fan needs to be nearer to the shower than the window.
Any ductwork in the loft needs insulating as cold onto warm equals condensation.

They need to rethink the whole thing.