Do bathroom humidistat extractor fans work ok

[AndyPRK]

I have a manrose fan humistat at the other end of the bathroom to the shower.

After a fair bit of tuning I am happy with its performance.

I have the fan connected to the light to trigger the fan at the start of the shower. (I find this necessary with my adjustments)

And then the humistat lets the fan run on for about 10-15 mins after the shower and light have been turned off.

 

[JohnW2]

I have the fan connected to the light to trigger the fan at the start of the shower. (I find this necessary with my adjustments) .... And then the humistat lets the fan run on for about 10-15 mins after the shower and light have been turned off.

A standard timer fan could surely do that without the need for a humidistat? - what are you gaining by having the humidistat?

Does the humidistat often turn the fan on at 'inappropriate' times?

Kind Regards, John

 

[AndyPRK]

Without a humistat I had to either :

a) Have the timer set to 10 mins which is annoying when your not having a shower.

b) Leave the light (and therefore fan) on for a long time after the shower.

With the humistat I just leave it to turn the fan off automatically.

With my humidity adjustment (because I thought it was leaving the fan running far too long - and almost getting stuck on) the sensor doesn't do a good job of automatically turning on. It will do, but by this time the room is too full of steam for the fan to cope with clearing it. So I therefore like to turn the fan on manually with the light.

 

[JohnW2]

Without a humistat I had to either :
a) Have the timer set to 10 mins which is annoying when your not having a shower.
b) Leave the light (and therefore fan) on for a long time after the shower.

Fair enough - so it's really back to that oft-asked question about how one can have a light-triggered timer fan which doesn't come on during brief visits to the room at night. As we discussed in a recent thread, there are seemingly some fans which have an on-delay (usually fixed at 2 mins) as well as a (adjustable) run-on timer.

Kind Regards, John

 

[AndyPRK]

I guess that's where the isolator switches are useful.

Switch fans off last thing and night.

Turn them back on when required.


or a timer in the consumer unit to feed all the fans in the house (but that doesn't work well with regards to isolation etc)

 

[JohnW2]

I guess that's where the isolator switches are useful. .... Switch fans off last thing and night. ... Turn them back on when required. ... or a timer in the consumer unit to feed all the fans in the house (but that doesn't work well with regards to isolation etc)

The first of those ideas is more hassle, and requires more memory, than most people probably want! Furthermore, for those who care, both of the ideas might be non-compliant in those cases in which the fans are required by regulations.

It's an oft-asked question (in one guise or another), and the fans with both an on-delay and a timed run-on would seem to be close to an ideal solution.

Kind Regards, John

 

[AndyPRK]

The on delay doesn't help remove smells. Depends what you want it for.

I'm sure a couple if buttons on the fan would be good though.

 

[JohnW2]

The on delay doesn't help remove smells. Depends what you want it for.

I would imagine that the on-delay is meant for 'nocturnal pees' (hence the usual fixed 2 min delay) and that they assume, rightly or wrongly, that generating smells(plus hand washing etc.) usually takes more than 2 minutes!

Any automated system obviously has to be a compromise to some extent (unless, in this case, there are any smellostats around!). However, I suppose one could have a manual pullswitch to over-ride the on-delay, for those who can produce smells rapidly!

Kind Regards, John

 

[AndyPRK]

Thanks for the info. I didn't know they had delays.

I have an airfreshner with odour detector so a little surprised they aren't in fans

 

[JohnW2]

Thanks for the info. I didn't know they had delays.

Most obviously don't but, as discussed here recently, a few do.

I have an airfreshner with odour detector so a little surprised they aren't in fans

Maybe some fans do, then - until a few days ago, I didn't know that the ones with on-delays existed, so I may have missed 'smellostat' ones as well!

Kind Regards, John

 

[ericmark]

I fitted a Humidity stat fan in my fathers bed room and it was a problem. It would turn its self on when shower was not being used. So I never fitted another.

As to humidity my meter only reads up to 95% and outside it does reach that quite often. At the moment 88% at 13.3 degrees. But inside Winter down to 31% Summer raises to around 60% with a few odd peaks where it's just under 70%. I would say 55% is a normal reading.

However we felt my father-in-laws house was damp and when tested yes it was. When I was reading 55% his house was reading 70% and house is nearly identical to ours but one person living there triple glazing never opens a window and cooks on gas.

I do think using electric cooking really reduces the humidity.

As already said if you pump air out it must be replaced. Not only through bathroom door but also rest of the house and we have tended to have better and better sealed doors to outside and the same with windows so it is easy to cause a depression through the whole house. With balanced flue central heating not too much of a problem but with any open flue fires one does need to be careful.

We have two velox windows in the kitchen with vents built in with these open and tumble dryer running we do not notice drafts through front door. However close these and we do notice draft from front door so clearly the air pumped out with tumble drier running causes a draft right through the house. Although rarely used we do have an open flue fire in the living room. So yes I would be worried if we did not have vents in velox windows.

 

[TanDiy]

Thanks for all the info. it sounds like humidity stats are not that reliable and I need to rethink this. it does not make too much sense to me putting in the fan on the light circuit. We would not need to put the lights on during the day and thus the fan would not be working if somebody showered. Likewise, we do not really want the fan coming on at night when nobody is using the shower. I understand that we need to have an isolation switch outside the bathroom - I guess we can simply use this to turn the fan on and off when required or maybe we can put a second Pull switch inside the bathroom. Thanks again for all the help and feedback.

 

[AndyPRK]

Maybe just fit one of these in the bathroom to do both jobs

http://www.ebay.co.uk/itm/FAN-ISOLA...ls_Supplies_Electrical_ET&hash=item439e1d4c06


An isolator in a cupboard sounds a pain (if you going to use it as an on and off switch too)

 

[Lectrician]

Ventaxia ambient response humidistats are excellent (but expensive). You need to position it (and your fan) were specked in instructions. The stat between the fan and the source of air (door for example).

I have one, and it turns on shortly after starting the shower, and runs on for around 10 mins, until clear.

I fitted a flow switch to the cold supply to my shower, firing the fan the moment the shower is turned on.

 

[arbitrary]

Apols if this reply is a bit late... fitted an Icon15 with humidistat some 4 years ago and v pleased with it. We use the pull cord to start it early and it then shuts off when the bathroom is dry - just like it says on the tin.

Only slight downside is that on wet and very very windy days the fan does occasionally switch on from humid outside air blown back into the duct. But as the fan is pretty quiet it's no big deal - I notice it but my partner doesn't. Will be installing another one shortly so that small downside isn't near enough to put me off.