Silavent Centrifugal Extractor Fan

[kevmcdo8]

Hi all,

I've recently bought a flat and have inherited a bathroom equipped with an old approx 25 year old Silavent centrifugal extractor fan which is not currently working. Also could clearly do with a clean!

I just wanted to check if (by my pictures), the wiring to the light is correct. My hunch is that it has just given up the ghost but the light fixture and wiring was a bit dubious so I'm not sure if the previous occupant has wired it back up correctly!


Thanks

Kevin

 

[JohnD]

The last picture suggests the wiring includes permanent live, switched live, and neutral. You can test this with a multimeter.

This is so the fan can include a timer, and run on for a timed period after the light has been switched off.

I can't make out from your bundle of wires if they include both L and SL. If they do, it is an advantage in a bathroom, as the timed period will help dry it after use. Your multimeter will tell you. It will also work on SL only, but without the timer.

You can get a modern fan to fit your 100mm duct that will be very quiet. You need one with a ball-bearing motor because it is mounted vertically. Can you find out the nominal air throughout of your old fan? About 80 cubic metres per hour is typical of a small fan. If you can get access to the duct above the ceiling you can fit a much more powerful, but equally quiet one.

 

[RF Lighting]

Without testing, it’s difficult to say for certain, but nothing looks out of the ordinary in your pictures.

 

[kevmcdo8]

The last picture suggests the wiring includes permanent live, switched live, and neutral. You can test this with a multimeter.

This is so the fan can include a timer, and run on for a timed period after the light has been switched off.

I can't make out from your bundle of wires if they include both L and SL. If they do, it is an advantage in a bathroom, as the timed period will help dry it after use. Your multimeter will tell you.

I think I saw Aldi have a budget meter in the Central Aisle this week.

You can get a modern fan to fit your 100mm duct that will be very quiet. You need one with a ball-bearing motor because it is mounted vertically. Can you find out the nominal air throughout of your old fan? About 80 cubic metres per hour is typical of a small fan. If you can get access to the duct above the ceiling you can fit a much more powerful, but equally quiet one.

The ducting is some sort of galvanised steel flat channel duct. I'm assuming it's because it's in flat and the void is so /narrow. I'm wondering if I can get some sort of adaptor from flat to a round 100mm duct to give me more options extractor-wise

 

[JohnD]

Might be similar to this one

https://www.fastlec.co.uk/silavent-...MIo_Hv0fLN6wIV2ON3Ch21ogeLEAQYAyABEgKObPD_BwE

Quite expensive but may be convenient if it is a straightforward swap.

80 cu.m/hr as I thought.

A bit low if you like steamy showers, but quiet enough to leave switched on.

 

[JohnD]

Yes, the adaptor is quite common.

https://www.tlc-direct.co.uk/Products/FD40710.html

I think I have also seen an elbow-shaped one.

As an example, this brand seems to me to be remarkably high quality and low noise. It has a nominal air throughput of 95cu.m/hr
https://www.tlc-direct.co.uk/Products/SLS100CRZ.html

There is an Envirovent 100 T which appears to be identical.

Cheaper fans are generally lower quality and lack the ball-bearing motor, rubber mountings, and backdraught shutter.

 

[kevmcdo8]

Bumping this as I replaced this unit back in September, but I recently have tried to adjust the overrun timer (as per the manufacturers instructions) to reduce the time but now the overrun does not stop when the light has switched off. I have to switch off the lights at the MCB to stop it. To be honest, I would be happier without the overrun. Is there a way of disabling this function?

 

[EFLImpudence]

Connect the Switched Live wire to both L and Timer terminal with a short link wire and put the Permanent Live wire in a connector block so that it cannot touch anything.

 

[kevmcdo8]

@EFLImpudence That sorted it! Thanks again!