I use may KE 100 on 8 radiators in my  summer house. When I install the  KE100 all works good and no error and right adapters. After a few weeks when I monitor the situation through the KASA app I can see that suddenly and randomly one KE100 open completely and push the temperature to 30 degrees Celsius thought the setting say 7 degreees Celsius. All KE 100 have new alkaline batteries that I checked was fully charged when installing in the KE 100. I then make a calibration and the temeperature return too normalish  about 3.4 degrees about wanted temperature. Ok a few weeks later a completely other KE 100 behave exactly the same, skyrocking temperature new battery and almost fixed with new calibration. Next time I was at the summer house I uninstalled all KE100 and reinstalled them and calibrated all and checked the battery standard all now looked good and I go home but suddenly after a week a hird KE 100 started to behave just like the others. I got a feeling the the engine inside the KE100 try to open little but it can not hold the pressure from the spring insside the valve and the KE 100 does not try to fix this unless you make new calibration. Why he get stronger with calibration I do not know. So is the valve spring in the radiator to strong for KE 100?