Manrose fan connection

The silly (but unavoidable) problem is, of course, that having an 'openable window' precludes the need for mechanical ventilation, even though there is no way of requiring the window to actually ever be opened!
That's OK - it balances out the situation of requiring a level of airtightness whilst not simultaneously forbidding opening windows or doors.

Chances are it is a 230/240V fan.

If it wasn't there would be a transformer somewhere.
Nobody has any idea if there is, or is not.

As the old fan has now been thrown away, and all that's left is a cable coming out of the wall, how can you say that there isn't a transformer somewhere?

I am not saying that at all. (Read the quote again.) I am saying if the fan wasn't 230/240V (and therefore 12V typically) then I would expect there to be a 12V transformer somewhere.

See what I mean?
No - you did not say "if... then...", you said "chances are...", i.e. you were asserting that it is more likely than not that is is a 230/240V fan.

I'll rephrase my question.

How can you say that there is a less than 0.5 probability (or less than 0.x, whatever you regard as the threshold for 1-0.x to be "chances are") that there is no transformer just because one has not been found, given that no search for one has been undertaken?

I said it was most likely the fan would be 230/240V.

I then said if it wasn't a 230/240V fan then one would expect there to be a transformer somewhere - indicating that the fan would be 12V if it wasn't 230/240V.

The op had removed the fan, and chucked it. So we don't know the voltage. Now if he knew of a transformer somewhere (not that he's been looking for one) then this may have given some indication to the voltage of the fan and the fan cable.

Last edited:
Now if he knew of a transformer somewhere (not that he's been looking for one) then this may have given some indication to the voltage of the fan and the fan cable.
Let's try again.

On what grounds do you assert that the fact that the OP does not know of a transformer means that the probability that there isn't one is >0.5?

On what grounds do you assert that the fact that the OP does not know of a transformer means that the probability that there isn't one is >0.5?
Maybe because 240V fans are more common than 12V ones?

Are they?

Unless there's been a sudden and dramatic increase in the proportion of 12V fans fitted versus 240V since I left Britain, I would say so.

Now if he knew of a transformer somewhere (not that he's been looking for one) then this may have given some indication to the voltage of the fan and the fan cable.
Let's try again.

On what grounds do you assert that the fact that the OP does not know of a transformer means that the probability that there isn't one is >0.5?

I'm saying that if there is no transformer present, this would indicate a 230/240V fan.

Whether he knows what a transformer looks like or where it may be is quite a different affair.

I'm saying that if there is no transformer present, this would indicate a 230/240V fan.
I know what you're saying.

What I've been trying to do is to find out why you think the fact that the OP neither looked for nor found a transformer means that there probably isn't one.

Well if there isn't one, then there isn't one.

I mean, if someone can confirm there is no transformer anywhere to be seen - then there ain't one.

One could trace the whole length of the cable, look in ceiling voids etc.

One could reasonably visually look all over for it.

Unless some goon has chucked it under a floor or something...

Maybe the correct thing for me to have said in the first place would be to test for voltage at the fan cable... perhaps that's what you wanted me to say?

Well - that would be a sensible thing to do for someone with the appropriate equipment and the appropriate skills to do it safely.

But it's not a case of wanting you to say, or not say anything - I just wanted to know how you got from the OP not knowing if there is a transformer to "there probably isn't one".

My experience ... I've probably replaced or attended to something like thirty or more bathroom fans. Out of all that, I've come across one ... yes one fan that was ELV.
All the rest 230/240v.

Well - that would be a sensible thing to do for someone with the appropriate equipment and the appropriate skills to do it safely.

But it's not a case of wanting you to say, or not say anything - I just wanted to know how you got from the OP not knowing if there is a transformer to "there probably isn't one".

Because 'there probably isn't one' if the fan was marked up 230/240V - but since he chucked away more research would be needed to verify what voltage the fan cable would be.

Thank you all for your help? Fan is now connected, I found a point in the wiring and ran an extra live cable to it. This forum has been very useful thanks to all your contribution

Thank you all for your help? Fan is now connected, I found a point in the wiring and ran an extra live cable to it. This forum has been very useful thanks to all your contribution

How did you run an extra live cable to it?

Do you mean you replaced the existing cable for a new cable with an extra core in it?

Or did you leave the existing cable in place, and run a seperate cable ?

If the latter, what type of cable did you use?

I used the existing 2 core cable and also added another 3 core cable to provide the extra live connection

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Replies
1
Views
8K
Replies
6
Views
18K