Replace micro switch

I plan to make an old converter element smart. It has a microswitch that can control on/off, can I replace it with any smart switch, for example one like this? SONOFF MINIR2 - Two Way Wi-Fi Wireless Smart DIY Switch

There’s a possibility that you need a smart switch with a potential free relay (also known as dry contacts) for such an application. Unless you have analyzed the circuit and are sure it doesn’t need a potential free relay, I don’t think the one you linked to should be used.

I’m not sure I understand completely. But I guess that I only need to be able to short the circuit and therefore need a simple switch that can open and close it? Would a Fibaro Smart implant work maybe?

I found a wiring diagram and it shows that the micro switch actually controls 230 V

If it’s a microswitch you very likely need a potential free relay. The Shelly 1 has one on board which can be used to switch 230V/16A, it’s very affordable, and has good Homey support.

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No, Fibaro Smart Implant won’t work as it isn’t specified for breaking 230V loads. I’m also partial to Shelly 1 or the Plus 1 that has replaced it.

Looking at the wiring diagram it is however possible to use a switch without dry contacts in your application but it must then be supplied from the same phase as the element, preferably by using the L from the terminal block (M) in the above diagram. Spend some time on drawing a diagram for yourself with the switch included and make sure that it’s possible to wire this up in a safe manner.

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Thanks for the good advice! So I should be able to get it together by using the same Load source that I also break to control on/off. I’m a bit unsure of what to do with N because it’s not used for the microswitch, but if it’s not required there it should probably work without it. If the Shelly needs it I can just use it from the terminal block i guess. But I’ll start by sketching the wiring as you suggest!

The Shelly (plus) 1 seems like a good option, thanks!

This is why I suggested you draw a diagram. Study it carefully and make sure you understand it, because your questions suggest you don’t quite have the grasp of how this works. There’s no room for guesswork when it comes to this stuff.
Even if you don’t technically need a potential free relay, it might be easier to understand how to connect it so Shelly Plus 1 should be a good fit.
No matter which smart switch you use, in this application they will need N.

Yes I will do that. I’ve installed a lot of dimmers and relays for lighting but this is kind of new to med so I will be careful. The Shelly Plus 1 seems like a good choice, with the addon for temperature sensors I can also connect them to the water pipes to get an even more precise control.

I just want to tell you how I solved it. I used Shelly 1 and powered it with the convector’s input current to L and N. Then I connected the wires from the microswitch (“com” to 1 and “co” to 0). I also connected the micro switch to L and SW. So now it works as a main switch (after I inverted the switch’s on/off in the app) and the Shelly can be controlled by my Homey.