So I created a new and easy automation for my warm water circulation pump- before it was just working with an old plug with a timer.
Now I use the the H2 power plug in combination with two presence sensors- one in my kitchen and the other in my bathroom.
The pump turns on by presence and turns off by absence. Easy and effective - just 
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Great! I guess this automation would help save on the electricity bill. By the way, the cat is so Chinese lol
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Easy but nice one. 
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Thanks for sharing! As said by yourself: easy and effective! 
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While it’s always interesting to see new automations, I would strongly advise against using presence sensors for a hot water circulation pump. In a plumbing setup, the circulation loop isn’t just a luxury for instant hot water, it is a critical safety measure.
By turning the pump off during “absence,” you are allowing the water to sit stagnant in the return pipes, cooling down into the 25–45°C range which is the ideal breeding ground for Legionella bacteria. In a system designed for circulation, these return lines can hold a significant volume of water that doesn’t get fully flushed out just by opening a tap. You’ve essentially turned your plumbing into a series of bio-reactors, and the moment a sensor triggers the pump, you are pushing that stagnant, lukewarm water directly toward your shower head.
It’s a fun automation to build and test for the sake of the “Smart Home” experience, but I wouldn’t recommend keeping it as a long-term solution. Safety and hygiene should always come before saving a few pennies on a high-efficiency pump.
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It’s actually hilarious when you think about it. Recently, a user from a Type E country (likely Belgium or France) was complaining about being forced to use the plug upside down because of the grounding pin. And here you are, with a German Type F socket and all the freedom in the world, choosing to plug it in exactly the way that drove the other guy crazy!
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Good morning!
I totally understand and got your concern! So you can make an additional automation- if there’s no movement for a specific time , the pump works for a specific time to move the water in the pipes
Of course there are always things you need to watch out in your habits and needs
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