Control bathroom fan separately from light without new wiring

I have one switch that sends a switched power line to the light. It then goes to the fan. I want to control the fan separately from the light, on a timer. So i need a wireless module that I will install in the fan box that turns the fan on and off. That module needs to be controlled by a switch not connected to the fan module with a wire, but RF or something.

The problem comes from the fact that some people think a single switch for the bathroom light and fan is ok. So they wire them from one switch. I think the fan should be controlled separately from the light. For example, I might want to turn the light off and have a timer leaving the fan on for 10 minutes. But there’s no wire to carry that signal, so I need a power on-off module at the fan that is controlled by a switch wirelessly.

Any ideas?

Dick F

Take the switch out of the equation by tying the wires together and putting a blank over the switch. Get a smart 2 switch relay module and tie one to the light and one to the fan. This will be located at the light/fan combo.

Get two battery operated smart switches and use a rule to turn on/off the individual relays. Or you could expand the box to two gang and hard wire two smart switches.

I got lucky where all of my boxes were wired for two loads. Even the rooms where there was only one light.


Ok. Yes. Thanks for this. I could connect the two wires together or probably do that at the light box. Then open that out to a double box and put in two smart switches there that would control two relays as you say. Just what devices would be best to use for the relays? I’d then like to create a virtual device so the fan could run for a timed period. Sound right?

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Fibaro, Monoprice, Aeotec all will work.