Newbie who wants to replace bathroom extractor fan

[Charlie_]

one thing worth considering, there is no other way that steam can exit the room.
do not expect any extractor fan to keep a room free of steam and moisture whilst you are having a shower or immediately after.

your room contains around 16,000 litres of air, assuming that you have a good supply of air into the room, either from a vent or under door etc it will take 15 minutes to do a complete air change of the room,
because of mixing of the air (dry air drawn in and damp air inside room) it will take 2 to 3 changes of air for the humidity to reduce to a low enough level to prevent condensation on cold surfaces.
your fan should be running on at full speed for 30 to 40 minutes after showering before the room will be dry.

if you are wanting the room to stay steam free whilst you are having your long hot showers, then I suggest a 300 to 400mm fan and ducting will be sufficient.
Note: it will be draughty and if the door is not closed properly it may pull open with the airflow!

If you go for the 300/400 fan I recommend you install a speed controller and also change direction.
In that way the fan can also be used to dry you off

 

[James]

If you go for the 300/400 fan I recommend you install a speed controller and also change direction.
In that way the fan can also be used to dry you off

how about this?

 

[telectrix]

how about this?
View attachment 49642

i'm more of a Pink Floyd and Deep Purple fan.

 

[coolsparx]

In a room containing a shower, I always recommend a 100mm mixed flow fan which is mounted in the duct, usually in the loft or occasionally in an adjacent cupboard. Standard axial fans extract 75-9o cubic metres per hour, compared to mixed flow at 240-260 cubic metres per hour. I used to fit the Vortice LINEO100T but now install the cheaper Addvent AVCIMF100T. These 2 fans are very quiet & because they are installed in the loft or an adjacent cupboard they are almost silent. I have installed a couple of Manrose mixed flow fans as supplied by customers but they were incredibly noisy & felt out of balance.

 

[Midwest]

Tosh.
Unless your talking monsoon rain forest, lightning & thunder shower , any decent fan will work. Also unless you have a bathroom the size Trump would have!