Quick question about the water leak sensor

Just starting to explore possibilities within smart things and I wanted to know if this scenario is possible

My idea was to replace my isolator to the extractor fan with a smart switch, have a water leak sensor in the bathroom with the idea that water vapor from the shower would hit the leak sensor and activate the fan.

No idea if this would work so thought I’d come and ask the pros

Thanks for reading

I think if you want to automate your bathroom fan, a better bet would be to use a humidity sensor.


Sadly vapour wouldn’t work, the water needs to join the two small contacts together so they complete the circuit to report “wet”.

As stated you could use something like a humidity sensor or most people just use their light switch as a trigger/condition and put it on a smart switch.

So when their light is on, it’s on and remains on 5/10/15 minutes after turning the light off.

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Wasn’t even aware that a humidity sensor existed. Do u have any that you’d recommend?

The fan does come on with the light at the moment but that’s where the problem is. The fan is quite loud and during the night when our baby is asleep it can wake her so I’ve been turning it off at the isolator but then when someone else goes for a shower they forget to turn it back on :expressionless:

What hub? UK or US? The devices are different for the two hubs.

The light solution could still work, just have it not apply during certain hours so it doesnt come on at night.


Thats a pretty good idea tbh. I have the UK version. Just had a quick Google search for one and found this https://www.amazon.co.uk/gp/aw/d/B0779BHQN3/ref=pd_aw_sim_60_of_46?ie=UTF8&psc=1&refRID=XB0AFSPYM9P5TPE2DS9K
One of the q and a’s says it can be connected to ST, then oddly… Another says it has a Chinese plug lol. Seeing how cheap it is tho I’m quite tempted to go about it with my initial idea. Now to search for a smart switch (another head ache according to the posts I’ve read on here)
Thanks for the help tho guys

what is an isolator? Looks like a UK jargon.

Isolator = big switch :slight_smile:


In electrical engineering, a disconnector, disconnect switch or isolator switch is used to ensure that an electrical circuit is completely de-energized for service or maintenance.
Very common in all Uk homes


I asked because “isolator” is still not clear if that is a double-pole or single-pole switch, or what.

“isolator” is uncommon in American electrical engineering and electrical work, so it sounds like a UK vernacular term. In USA it’s usually “disconnect switch” or “disconnect” (noun). A disconnect may break just the energized lines or it may break all except ground.

another reason to tag posts by country.

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