Switching non timer extraction fan

[sparky1508]

Hi,

Can't seem to find anything in the regs but I have been asked to fit an extractor fan in a small cupboard containing some IT equipment which gets quite warm and it's just to dissipate heat out of the cupboard. My question is, as it's a fan without run on timer I am using T&E to power it and just wondering of its ok to use a standard 10 amp one way switch to isolate. Just wondering if I need to wire it so to isolate both line and neutral or whether it's ok to just isolate the line conductor as I don't seem to be able to source a double pole switch under 20 amps.

Thanks

 

[polo1]

Many manufacturers require fusing down to 3 amps. Are you taking a feed from lighting or power circuit - if the latter, it'll need fused down anyway? Doesn't require DP switching/isolation imo.

 

[Bobster]

Would it not be prevalent to wire this fan through a thermostat. This way it doesn't have to run 24/7

 

[tony mc]

If the manufactures want the fans they sell fused down to 3 amps why dont they build them into the fan,surely the fuse is there to protect the cable ?

 

[Flanders]

Would just one extractor do the job as you will need air flow in and out of the server room to cool it down and I would not think running a small extract fan for a long time would last very long, as they are normally only on for short periods of time may be worth checking the manufactures Instructions.

 

[sparky1508]

It will be wired from the lighting circuit and she wants it to run 24/7 unless she decides to switch off. Still waiting for supplier to get fan so don't know yet if manufacturers state fusing or not. Will have to make that decision at the time. Don't suppose I could use a 20 amp switch fuse with 3 amp fuse to cover all bases.

 

[sparky1508]

Would just one extractor do the job as you will need air flow in and out of the server room to cool it down and I would not think running a small extract fan for a long time would last very long, as they are normally only on for short periods of time may be worth checking the manufactures Instructions.

It is just one fan and also fitting a air transfer grill in the door to let cool air in.

 

[Octopus]

Use a dp grid switch?

 

[sparky1508]

Use a dp grid switch?

Looking at those they are all 20 amps so might as well just use standard DP fused switch if 20 amps is ok to use, it would have 3 amp fuse in it. If manufacturer doesn't state fusing then is it ok to use standard 10 amp single pole switch?

 

[Octopus]

Looking at those they are all 20 amps so might as well just use standard DP fused switch if 20 amps is ok to use, it would have 3 amp fuse in it. If manufacturer doesn't state fusing then is it ok to use standard 10 amp single pole switch?

Just use a S FCU with a 3A fuse in it!

 

[Flanders]

It is just one fan and also fitting a air transfer grill in the door to let cool air in.

Ok but still unsure if you should have a fan running constantly Rob's suggestion of a Thermostat is a good idea

 

[ruston]

I would go with Rob's suggestion. running 24/7 may be unnecessary , depending on the usage and situation.

 

[sparky1508]

I would go with Rob's suggestion. running 24/7 may be unnecessary , depending on the usage and situation.

Definitely a good idea and the IT equipment is on and running all the time. Will look at puttin it on a thermostat and get back.

 

[Octopus]

I hope the customer isn't going to expect you to fit a £15.00 fan from a shed - I doubt it would last very long being switched on all the time!

 

[Flanders]

I hope the customer isn't going to expect you to fit a £15.00 fan from a shed - I doubt it would last very long being switched on all the time!

That what I said in Post #5