Extractor fan wire

Rualahmed

Can kindly someone explain 
what these wires 
& why I have 2 red wires & 1 black wire from mains line connecting to extractor fan in loft  

the 2 red wires confuse me 

I’m trying to replace with a timer extractor fan 

thanks 

littleboo

For a fan with a timer, you have a permanent live and a switched live. Are you saying the current fan does not have a timer?

Bendy_House

The existing one appears to have a timer too.

Rual, have you COMPLETELY isolated the power to that extractor? I don't mean the switch that turns the extractor on and off, but the 'proper' isolating switch which supplies it. This dedicated switch usually looks like a wide light switch, and should have 'extractor' on it. This SHOULD isolate BOTH these red wires, but you should really turn off the correct MCB in the consumer unit as well. And then TEST the wires!

(When testing wires for being 'live', whether using a neon screwdriver, volt stick or test meter, you should also test the tester itself by proving that it works, and then turn the power off!  Safely, of course...)

Back to these wires. One is 'permanently' live ( whenever the isolator switch is on), and this is used to KEEP the fan running via the timer, even after the 'fan' has been turned 'off'. So remember that turning 'off' the fan once you have exited the loo does NOT cut the power to the fan.

The other red is the 'switched' live, ie the one that comes on whenever you turn the fan on via the pull cord or whatever.

Which one is which, I don't know, but you should be able to test this easily using your tester. Or look up the EXISTING model of fan, and see if it's the red or brown.

Or wait for someone on here who knows!

Once you work it out, it's worth labelling the wires before you disconnect them; 'Perm Live' and 'Switch Live'.

Do the testing of these wires whilst they are still screwed in to their terminals, and not when they are loose...

Rualahmed

Thanks for the advice , 
that’s what I thought as well 

need to test which ones which 

thanks