Bath extractor blowing cold air

[Jupiter01]

I’ve got one of these that is blowing air into the bath.

However, when I place a tissue on the fan it does suck it in. Defies logic!

There’s lots of water sitting on the bath walls.

Can I get some advice on this muddled situation I find myself in please.

 

[Jurassicspark]

What type of vent is on the outside?

You can find vents with shutters that block cold air coming from the outside.

There’s lots of water sitting on the bath walls.

Is the fan controlled by a timer? How often is it used? Have you got a air gap below the door?

 

[ChrisJP]

Do you mean that when the fan is OFF you get cold air blowing into the bathroom, or do you mean when the fan is ON it's blowing air into the bathroom instead of sucking it out?

 

[Jupiter01]

Do you mean that when the fan is OFF you get cold air blowing into the bathroom, or do you mean when the fan is ON it's blowing air into the bathroom instead of sucking it out?

When it’s on, it’s blowing air into the bathroom

 

[Jupiter01]

What type of vent is on the outside?

You can find vents with shutters that block cold air coming from the outside.


Is the fan controlled by a timer? How often is it used? Have you got an air gap below the door?

Not sure about the vent in the outside. It has a 10 min over run. We have a gap under the door.

 

[Jurassicspark]

Since when has this occurred?

 

[Burnerman]

Has someone reversed the impeller?
For sure mr J, you do keep us on our toes - absolutely no disrespect intended here!
John

 

[ChrisJP]

Has it been rewired recently? The impeller and motor are running in reverse so may be wired incorrectly.

 

[Burnerman]

I didn’t think these AC motors could be wired to reverse?
Intrigued!
John

 

[RandomGrinch]

The impeller and motor are running in reverse so may be wired incorrectly.

I think that would be unlikely, given...

when I place a tissue on the fan it does suck it in.

If this has recently started and you haven't noticed it before, it may be possible that there's a partial obstruction to the flow.

Not sure about the vent in the outside.

If the exterior vent has shutters, have a look to make sure they open and close prooerly, when the fan is operating.

 

[Harry Bloomfield]

A powered shutter opening, with fan blades not turning/seized, would allow cold air in!

 

[RandomGrinch]

I didn’t think these AC motors could be wired to reverse?
Intrigued!
John

Yes, a single phase induction motor (as typically used on these fans) wouldn't change its run direction, simply by swapping the wires around.

 

[StephenStephen]

Given that it sucks a tissue towards it, what is happening to make you think it is blowing air into the bath? (bathroom?)

 

[Jupiter01]

It hasn't bene rewired recently and has been in place for a few years. I only noticed the surface water this winter and the blowing last year. The reverse impeller sounds very plausible. Except the tissue does get sucked in when I try this. I do find that odd.

I can feel the air blowing by putting my hand near it. It has a fan-like effect.

Would it help to post a picture of the wiring? Thanks for all your help.

 

[Harry Bloomfield]

I can feel the air blowing by putting my hand near it. It has a fan-like effect.

Because it is a fan, perhaps?