Bathroom fan inefficient

[IfYoureHappyAndYouKnowIt]

I have recently moved into a new house with a small bathroom with a shower. There is an fan on the external wall which goes on and off with the light switch.

It seems very inefficient to me, the room becomes very wet when showering and takes a long time to dry.

I'm assuming that I need to replace the fan and have googled opitions. But I can't quite figure out what would be best. Can you help?

if the fan is not over the bath then you do not have to get a waterproof or low-voltage fan, so you have a wider choice.
I couldn't see which fan you currently have, see if you can identify a similar one on any of my links.

A bathroom fan works best if the door and window are shut, as it causes suction in the room. Replacement air will come in through the gap under the door.

We have a humidity controlled fan -would that work for you?

I will try and post a decent link to the fan. Don't seem to be able to post a prettier link on mobile app.

I'm sure I could get a humidity controlling one but I'd really like to identify the problem before I buy anything so that I can be sure I solve the problem. I've not had a problem like this before in any previous properties so I'm wondering whether the problem is a faulty fan or something to do with the room.

I will try and post a decent link to the fan. Don't seem to be able to post a prettier link on mobile app.

I'm sure I could get a humidity controlling one but I'd really like to identify the problem before I buy anything so that I can be sure I solve the problem. I've not had a problem like this before in any previous properties so I'm wondering whether the problem is a faulty fan or something to do with the room.

We had a major problem with condensation in the bathroom last Autum, basically wet walls 24hrs a day.
Remedial services checked wall temperatures which were very low despite constant heating, not surprising since house is very old and 2 of the worst affected walls were external.
They reccomended a humidity activated fan and to not open the windows is cold weather as this makes the walls colder, thus drawing moisture onto them quickly.
The humidity fan has reduced the condensation dramatically.
I don't have to wipe the walls down at all so I would reccomended that tbh.

Thanks that's interesting. It is an older house. And the bathroom does have two external walls and an old single glazed window...