Vent-Axia Bathroom fan - spins very slowly/loudly, but under timer works fine?

[Ned2020]

I've got a Vent-Axia ceiling extractor fan in the bathroom (about 3 years old). It runs when the lights are switched on in the bathroom, and then for a further two minutes (on a timer) after the lights are switched off

It has recently started to make a lot of noise and spin very slowly, but when the lights are switched off and the two minute timer keeps the fan alive, it runs fine

Any suggestions welcomed!

 

[Harry Bloomfield]

Has it always behaved like that, or is it a new problem?

 

[conny]

Are you saying it runs noisily when the light is on but goes quite when the fan is on over-run time?

@Harry Bloomfield, it's recently started doing this apparently. It's been fine for 3 years.

 

[RandomGrinch]

Can you take the bulbs out of the light fitting and see if it still happens?

 

[Harry Bloomfield]

Can you take the bulbs out of the light fitting and see if it still happens?

We have the same thought!

 

[Ned2020]

Six recessed lights in the ceiling - would be a pain to take them all out just to test it

When the lights are on the fan is noisy and turns very, very slowly - you can see the blades

As soon as the lights are turned off the fan behaves normally for the next two minutes until it switches off automatically (timer).

Trying to understand if the fault is with the fan, or with the wiring

 

[Harry Bloomfield]

Trying to understand if the fault is with the fan, or with the wiring

It reads as if the light(s) might be in series with the fan, when the lights are on. So yes - something amiss with the wiring.

 

[EFLImpudence]

It has recently started to make a lot of noise and spin very slowly, but when the lights are switched off and the two minute timer keeps the fan alive, it runs fine

 

[Alec_t]

The mechanical switch itself could be faulty, presenting a high impedance to the fan. Methinks the timer has a solid-state switch which presents a low impedance to the fan.

 

[Harry Bloomfield]

The mechanical switch itself could be faulty, presenting a high impedance to the fan. Methinks the timer has a solid-state switch which presents a low impedance to the fan.

The mechanical switch is common to both the fan and the lights..

 

[RandomGrinch]

We have the same thought!

Turns out my thought wasn't quite the same as your thought!

Six recessed lights in the ceiling - would be a pain to take them all out just to test it

Ok, could you temporarily disconnect the wire (and safely isolate it) from the Ls terminal of the fan, and add a small wire link between the Ls and L terminals, and see if the same thing happens?

 

[Harry Bloomfield]

Ok, could you temporarily disconnect the wire (and safely isolate it) from the Ls terminal of the fan, and add a small wire link between the Ls and L terminals, and see if the same thing happens?

Or, if you have a suitable test meter...

Check and report the voltage between N and Ls, with the light switch turned on.

 

[conny]

Have the downlighters been changed to LED's or extra low voltage type? Could it be driver incompatibility?

 

[george.eames@thomase]

If you put a piece of toilet paper by the extractor fan while it is running, does it hold it?

 

[David White]

Hi NED 2020.

Did you get this resolved. It sounds very simiar to the problem we have. When the light is switched on the fan sounds like it is turning very slowly but when the light is turned off the fan speeds up albeit a bit hesitantly at first, but then it only stays on for a short time. I thought it was water getting caught in a low point in the ducting, but there was none.