Donwill wrote:
At the moment it's running at a single high speed and is quite noisy.
How do they work? I note that there are three leads coming from the fan
motor, two of which are connected i.e red & blue. The third is white and
isn't connected to anything, I assume it's a tapping on to the field coils
to reduce the magnetic field, and cause slippage to slow it down. would this
cause the motor to run at a higher temperature? or am I barking up the wrong
tree here. I'm loathe to try connecting the white lead without some
guidance.

Don

You're really not giving enough info here. If you want to quieten it
down, a series dropper is effective. There are also several other
ways:
http://www.wiki.diyfaq.org.uk/index....oise_reduction


NT