Isolator on extractor fan

[JohnD]

With luck your hearing will go as you age, and you won't notice it.

 

[securespark]

Pictures of the fan and the situation would be a great help.

 

[JohnW2]

The simple choice is, either a slight bit of noise from a fan, or a bathroom filled with moisture and mould developing.

Up to a point, but many of those expecting an extractor fan to cure their mould problems will end up disappointed.

Probably more important is to try to avoid their being cold walls and ceiling when there is steam around (e.g. when having showers) - since once water vapour has condensed on those surfaces (there to promote mould), a fan will do almost nothing to remove it!

 

[Harry Bloomfield]

Probably more important is to try to avoid their being cold walls and ceiling when there is steam around (e.g. when having showers) - since once water vapour has condensed on those surfaces (there to promote mould), a fan will do almost nothing to remove it!

Few will enjoy having a shower in a cold room, so it's a fair assumption the room will be reasonably warm - which just needs the use of a fan, to extract the moisture, before it eventually condenses out on the walls.

 

[JohnW2]

Few will enjoy having a shower in a cold room, so it's a fair assumption the room will be reasonably warm - which just needs the use of a fan, to extract the moisture, before it eventually condenses out on the walls.

It obviously 'depends', but quite a lot of bathrooms and shower rooms, particularly small ones, are fairly poorly heated, not uncommonly only by a heated towel rail (or, sometimes, the dreaded underfloor heating!).

Whatever the theoretical discussions, I have certainly seen many cases in which an extractor fan, alone, has not cured a mould problem.

 

[Harry Bloomfield]

Whatever the theoretical discussions, I have certainly seen many cases in which an extractor fan, alone, has not cured a mould problem.

Ignoring personal comfort, concerned just with mould - if the choice were between heat, or a fan, then I would choose the fan, as the more effective solution.

 

[JohnW2]

... if the choice were between heat, or a fan, then I would choose the fan, as the more effective solution.

I wasn't suggesting a choice ('either/or'). Rather, I was suggesting that if one installs only a fan without also ensuring that the walls and ceiling are pretty warm when taking showers, one is quite likely to end up disappointed in relation to the effect on mould.

 

[JohnD]

Up to a point, but many of those expecting an extractor fan to cure their mould problems will end up disappointed.

Probably more important is to try to avoid their being cold walls and ceiling when there is steam around (e.g. when having showers) - since once water vapour has condensed on those surfaces (there to promote mould), a fan will do almost nothing to remove it!

When I had CWI installed, the bathroom (on a corner) got much warmer and drier, with the same existing radiator and fan. I don't even get mist on the bathroom mirror now.

 

[Harry Bloomfield]

I wasn't suggesting a choice ('either/or'). Rather, I was suggesting that if one installs only a fan without also ensuring that the walls and ceiling are pretty warm when taking showers, one is quite likely to end up disappointed in relation to the effect on mould.

I was trying to point out, that the extraction of moist air, is more important than warmth in the fabric.

 

[SUNRAY]

I was trying to point out, that the extraction of moist air, is more important than warmth in the fabric.

That assumes the air change is fast enough and adequate fresh air entering otherwise warm surfaces play an important role.

 

[JohnW2]

I was trying to point out, that the extraction of moist air, is more important than warmth in the fabric.

I'm not sure how either of us can be very sure about the relative importance of those two things. What we may be able to agree on is that it is better to address both than just one?

As I said, I've certainly seen many examples of installation of a fan (alone) not doing much, if anything, to alleviate a mould problem - haven't you? I suppose that one doesn't need any more than eyes to assess the situation - if, after installing a fan, there is still condensation appearing on walls and/or ceiling, then I suspect that any mould problem is likely to persist.

 

[SUNRAY]

I can only look at this from my experience in the controls industry, in situations where warm moving water is likely the air temp is commonly set at a minimum of 2 degrees higher than the water temp.

 

[JohnW2]

I can only look at this from my experience in the controls industry, in situations where warm moving water is likely the air temp is commonly set at a minimum of 2 degrees higher than the water temp.

What do you mean by 'warm moving water' - do you mean 'in pipework'?

 

[Harry Bloomfield]

I'm not sure how either of us can be very sure about the relative importance of those two things. What we may be able to agree on is that it is better to address both than just one?

As I keep repeating, we have no mould issue here. We did have a very slight issue, with a tiny amount in the ceiling corner, until a few years ago, but I addressed that. It's obvious now, what the issue was....

I had installed a bathroom wall fan, PIR, and humidity sensor, with a timer - but I had lazily installed it in an existing through the wall, double brick air vent, simply enlarging the holes in the brick vent, with a drill, assuming that was enough. Obvious now - it was causing a lot of back pressure. It was fitted in a bit of a rush, when I had the original SG windows replaced, with DG. The original SG window pane, had been fitted with one of those pointless, unpowered, spinning, plastic fan vents. Back then, we certainly did have a problem with mould.

Since then, I actually got around to making a better job of it, cutting the centre out of the brick vent, and fitted a proper, self-closing, outside terminal. The tiny amount of mould, in the corner disappeared, and has not returned, so I have to surmise, it was due to the extra air-flow, via the fan.

Our bathroom is not maintained, particularly warm - usually between 14 and 18C. It is formed of two outside walls, one with a window. So I maintain, that good extraction, is much more important than temperature. Even in a warm bathroom, the walls will always be cooler, providing an opportunity for it to condense out, on the walls, unless quickly extracted. Extract the moist air, quickly, whilst it is still airborne, before it can settle on the walls.

As I said, I've certainly seen many examples of installation of a fan (alone) not doing much, if anything, to alleviate a mould problem - haven't you? I suppose that one doesn't need any more than eyes to assess the situation - if, after installing a fan, there is still condensation appearing on walls and/or ceiling, then I suspect that any mould problem is likely to persist.

I don't visit many of other people's bathrooms, why would I? What I do, do is read lots of complaints of mould on here, it the cause always seems to trace back to poor ventilation of bathrooms, rather than lack of warmth.

 

[SUNRAY]

What do you mean by 'warm moving water' - do you mean 'in pipework'?

Exposed water which gives rise to wet air such as bathing areas.