Noisy Bathroom extractor Ask questions and find answers to many subjects relating to electrics and electrical work

[sentoffagain]

I have a noisy motor in the extractor fan. Rather than replace the fan I thought I could put a dimmer switch in place of the isolator and slow the motor down. Is it as easy as just buying any old dimmer switch or have I over simplified matters?
Cheers,

[ericmark]

Over simplified as many motors are dependent on frequency of supply to what speed they run not power supplied and you would need an inverter at about 10 times price of new fan to control it's speed. Brushed motors may be controlled by wave form clipping devices but not the brushless type.
Eric

[sentoffagain]

Thanks ericmark, you say most motors, what do I need to establish from the extractor fan to enable me to replace the isolator with a dimmer switch or are you saying there is not a hope in hell of me being able to do this and just find a quiet extractor fan to fit the same hole?
Many thanks,

[mephistico]

I wouldn't bother wasting time and effort messing with dimmers. What you would need would be a speed controller but for a domestic situation, it's hardly cost effective.
What make is the fan?

[charliewm]

Do not use a dimmer switch as the motor will fail.

[sentoffagain]

Hi, It's a Vectaire "A" Axial Style.

[mephistico]

Easy to replace this with a Manrose or similar make. I presume it's 4"?