Bathroom extractor Fan - Advice needed!

[HAMUHU]

Hi all,

My bathroom is a hot bed for mould and condensation. we only have a small window so we need to install an extractor fan. however, i am confused. Here is what i know:

1. One connected with light switch, turns on, then turns after a few minutes of turning light off
2. Pull cord - self explanatory!
3. Humidity sensor - this is automatic depending on humidity level.
4. Humidistat and Timer - i think this is linked with light switch but not sure how its different from no.1 above.

then you have the centrifugal fans and axial fans???

can someone help me out here??? the mould/condensation in my bathroom is quite bad now so i do want a decent one. i don't want to spend more than £250 including fitting. a days labour where i live is about £130 (northwest england).

HELP!!

 

[PrenticeBoyofDerry]

1. One connected with light switch, turns on, then turns after a few minutes of turning light off

They have any overrun on them that can be adjusted, you will require 3 core and earth from light fitting and a wall mounted fan isolator.

2. Pull cord - self explanatory!

Generally on/off with no overrun

3. Humidity sensor - this is automatic depending on humidity level.

It is what it is will come on when the humidity level rises to the design level

4. Humidistat and Timer - i think this is linked with light switch but not sure how its different from no.1 above.

Has both an overrun from light being switched on and humidity senors that will automatically operate when level rise.

then you have the centrifugal fans and axial fans???

Different mechanical methods of dissipating the air, it is most common that an axial fan would be used in a domestic dwelling.

Remember that the fan size should be chosen by the room size
http://www.tlc-direct.co.uk/Technical/Ventilation/Ventilation4.html

 

[foxhole]

I use a 6inch fan mounted inline in loft and connected to twin inlets in shower room this prevents any condensation and as room has no window connected to sensor which turn both fan and lighting on , has a timer fitted.
I don't like humidistats as they require moisture to trigger, but that's too late you want the fan removing air before there is any build up.

 

[ericmark]

Pneumatic push switch is what I would use. I don't always shower at night and would want the fan to work during the day too.