The automatic fill valve needs the expansion tank to have the correct air pressure in order to function properly. I installed this specific thermostat and couldn't bring it to the required 1.5 bars for the closed water circuit to work. I realized that the expansion tank had no air at all inside. When I added 4 bars, which my 20-liter tank required, the automatic fill valve worked correctly.

Although it was advertised and recommended to me as the best, it didn't hold up!!! Expensive and lousy.... Two years of constant problems, I replaced it

It comes pre-set at 1.5 bar and you put it on top and it reaches the pressure of the network! I managed to reach 1.6 by turning the regulator to 0.4 without stopping the filling!

In the end, the regulator was replaced with FAR as there was obviously an internal leakage in the O-ring, resulting in it not stopping the filling

Out of the 10 I have purchased, 8 did not last more than a year. Not to mention that half of them had issues from the beginning. It doesn't mean anything to me that the company replaces it because they know it's faulty. My effort and my money are wasted

It does not stop at the required setting unless it closes from the spout (the closed circuit is controlled and the expansion tank is checked). The rating is relative to many different hydraulic products, I would prefer a different brand but also heavy-duty type