12v Bathroom fan to 240v fan

[ihatesheds]

Howdy,

I realise that there are a few of these posts already, but I wanted to be 100% before I started doing things!

A couple of years back I went to change some weak bathroom fans for something better, didn't realise I'd got 240v instead of 12v
I'd planned to leave it to my sparky but he never came back to me and then I left it 2+ years. Things came up and 2 weak fans went way way down my list of priorities.
But I've now got to that point on my list

Pictures should help with my descriptions I hope!

Current fan position is dire for getting steam out of the room, combo of position and it's really weak.



I've been looking at 12v fans and I can't find one I like that the wife will sign off on.


My 240v fans have humidity sensors and timers and other stuff I honestly don't care about, we can turn it on and off as needed. They were way past the return point when I first tried to fit them, I might as well just use them now.

My plan is to gut the old transformer and link the cables together


I suspect I then need to link the L to LT with a bridging cable?
The fan is rated IP45 for zone 1 without a 12v transformer



My question/concern is the cable running from the transformer not being the right cable, as if it isn't it's a much bigger job to do as it's buried in the wall/ceiling from what I can work out.

Have I missed anything obvious?

Thanks in advance!

 

[Murdochcat]

If that fan is opposite the door it’s probably in the best location

Are you sure you are getting enough air flow into the room under the door?

 

[ihatesheds]

If that fan is opposite the door it’s probably in the best location

Are you sure you are getting enough air flow into the room under the door?

The door is 90 degrees to it on the right
Opposite the door are cupboards that get condensation all the time in winter.
I've coated them in heat retention paint and then bathroom paint and it's much better but airflow is not great in there unless I pop the velux window, though we live on the top of a hill and it gets battered too much in winter to leave it open for long.

 

[Murdochcat]

Do not open the windows

Shorten the door

 

[ihatesheds]

Do not open the windows

Shorten the door

When the room is full of steam I don't want it venting into the bedroom though. Our wardrobes are right next to the door.
The door already has pretty good airflow too.

If you're in the shower for more than 3 minutes the entire room fills with steam, which is why I am looking at the fan. I can't find the make to be sure but it's airflow is next to nothing.

 

[flameport]

My question/concern is the cable running from the transformer not being the right cable,

Looks to be standard flat T&E, as used for any other 230V circuit.
Only has 2 cores so the fan would need to be controlled from the isolator or some other switch, but certainly no problem in using the existing cable.

 

[Murdochcat]

When the room is full of steam I don't want it venting into the bedroom though. Our wardrobes are right next to the door.
The door already has pretty good airflow too.

Does the fan hold a piece of toilet paper to it when it’s on?

And why would the steam go into the bedroom?

 

[ihatesheds]

Does the fan hold a piece of toilet paper to it when it’s on?

And why would the steam go into the bedroom?

Barely, if you hold your hand to it you can feel a very faint sucking of the air.

Opening the door to improve airflow. The space underneath is enough, you can feel it on your feet if stood next to it.

 

[Murdochcat]

So what happens the other side of the fan ?

How long is the vent pipe?

What type of wall grill do you have?

How long does the timer run for?

 

[ihatesheds]

So what happens the other side of the fan ?

How long is the vent pipe?

What type of wall grill do you have?

How long does the timer run for?

Can't get that high without a ladder but you can see steam coming out when it's super cold

I'd say 60-70cm without having measured it

Normal one that flaps in the wind.

A few minutes, probably 5

 

[Murdochcat]

Timer needs to be much longer and yes I would increase the gap under the door to 6 mm

Do not open the window