Timed Fan - How to Wire a Bathroom Extractor Fan with Timer

Summary: Connecting a timed fan unit - how to wire in a new bathroom extractor fan with timer. Use this clear wiring diagram of how to connect up your timed fan to ensure you install your timer fan successfully.

Don't want to do this job yourself? Let us help you find a tradesman local to you

Fans with an integral timer need a 3 core and earth supply to allow the unit to run on after a light is switched off. It must also be possible to isolate the fan by means of a pull switch inside the bathroom, or a fan isolation (3 pole) switch outside of the bathroom.

Before attempting fan or any other electrical connection ensure all circuits are off.

Isolation switch for use in bathrooms and special areas for isolating circuits

Isolation switch must be on a pull cord inside a bathroom or as above a switch on the outside.

 Diagram showing wiring method for a timed fan

  • D = Earth Connection = To all units…This wire should be sleeved in a green/yellow earth sleeve.
  • C = Neutral Connection = To 3 & 6
  • A = Permanent Live Connection = To 2 & 5
  • B = Switched Live Connection = To 1 & 4

For regulations governing heights of sockets etc, please see our Socket Height project page

You might be interested to go to our video section on installing ceiling fans to watch a film on "ceiling fan installation".

Don't fancy doing this project yourself? We work with Checkatrade to ensure that we recommend only reliable and trustworthy tradesmen.

All project content written and produced by

Project Feedback