Surging Manrose timer fan in a bathroom Ask questions and find answers to many subjects relating to electrics and electrical work

[Lewie]

Hi all
I have a Manrose timer fan in a bathroom. It’s started ‘surging’. I switch it on and it either buzzes and sounds like it’s struggling to turn, or ‘surges’ like it is being switched on and off, again with a sense of struggling to get going. The surges vary on how long they last. Sometimes it eventually just runs normally, sometimes it surges until it’s switched off. Either way, as soon as it switches off, the timer side of things runs perfectly. It’s probably 4 years old and needs replacing but thought I’d make sure there isn’t a simple solution. I’m also interested in what causes such behaviour. Cheers

[Mr White]

It's "old age" its bearings will be on the way out, no user serviceable parts.

[Lewie]

Thanks for the reply Mr White.
Though I disagree with your diagnosis.
If it is the bearings it wouldn't run perfectly on timer.
I'm thinking it's electronic.
There must be two different circuits.
One for normal running and one for when it switches over for timer.
I'm wondering if there is a diode (or whatever) on it's way out?
Any electronics experts about?
Just interested really, though if it's easy to change...

[Mr White]

You know what you were trying to convey, (I do not) to me, it was not clear that it ever ran freely. That aside, ideally you would need a circuit diagram to use as a reference point to check the value of each component. (Or you get lucky and find a burnt component) But to pay an "electronic expert" to do look at it would cost more than a new fan. Manrose do supply a replacement timer, but to buy one is 1/2 -2/3 the cost of a new fan (Depending on which fan you have) but in the long run it will be easier and quicker to change the whole fan.

[Lewie]

As I stated in my first post, "Either way, as soon as it switches off, the timer side of things runs perfectly"
Not sure how much clearer I can be, but hey!
As for an electronics expert, I was asking if there was one about on here.
Of course paying to have a £30 fan diagnosed would be ridiculous.
Also, again as I stated, I was just interested.
I have since bypassed the circuit board and the fan runs just fine, so the bearings diagnosis was incorrect.
And yes, I can see exactly which component has burnt out.
Thanks for your suggestions. I will try and get a replacement capacitor (or whatever it is) and try it, again, just out of curiosity.
I had a LCD TV pack up, spent a few quid on capacitors. soldered them in and it works just fine.
It's good to learn.

[HarryGarcia]

Thanks for the info, I appreciate it. I will keep it in my mind.