Unacceptable, the transmitter does not communicate correctly with the base, it turns on and off whenever it wants regardless of how you set the thermostat. This happens very often and most importantly, there is nowhere to take it for warranty/inspection...there is only a phone number where they handle everything. And if you want to send it for inspection because the excuses for how it operates do not convince you that they are normal, the official Siemens will ask you to send it back to where you bought it (since there are no offices, nothing) along with 20€. Yes, you understood correctly, that's how the warranty works after payment...the money will only be refunded if it is proven to be defective... But what defect, since all the excuses they have given over the phone are normal and even if you have sent them videos showing that it does not turn on or off or turns on when it shouldn't, etc. Something that they do not mention anywhere in any product description. I have never experienced this in any other case...

Excellent product for its job but with ridiculous drawbacks that I deduct two stars because they are really ridiculous and they should include them in the next models, come on, it would have a 5€ difference.

I bought it because the thermostat base was above the collector and in order not to drill walls, I bought a wireless one.

I chose this one because it doesn't have a differential (ON/OFF at a distance e.g. 0.3 from the desired temperature) and instead it uses the TRI algorithm, which basically even if you have 22 on the counter and 30 in the house, if it drops rapidly to 25 in the house, it will turn on to mitigate the drop. Forget everything you knew about thermostats, as if it reaches the temperature, it makes consecutive small movements (economy) to maintain the temperature and not feel the heat now cold as soon as it closes. Neither in the opposite case, to burn the bodies until it reaches temperature, it closes it enough before it doesn't go above the desired temperature.

I solved some tremendous problems but the drawbacks for a 100€ thermostat are tragic and ridiculous.

1. It doesn't have lighting. Okay guys, it's wireless, if I have it in my room at night what will I do? Are we serious? Who thought of this?

2. It doesn't have anything more than 0.5. Okay luckily you don't feel this difference, it's a small crime, but let me choose 21.3. Besides, it doesn't even show the room temperature and compared to the old thermostat, it's different.

Happy with my choice, I recommend it everywhere but it's worth 3.5 stars because it doesn't do anything spectacular.

Oh, the photo is wrong, it's the one with programs on the right, what it shows is the RDH100RF not the J.

edit After 2 years of use, I have to say... DIFFERENT HEATING LEVELS. And without light, and without 0.3, no problem.

edit For k11_antonis who writes in a comment that it turns on when it shouldn't: Dude, that's how TPI works, if you have 30 in the room and you have it at 15, if the temperature drops abruptly, it will already start to turn on at 25