@Muesli Half a degree doesn't seem at all unusual. Does it move an higher than that?
@Mansell Does it stay that far out or go to 22.7 and then flatten out?
@Mansell I've seen images on here - try copy and paste?
I am not sure if this April 2019 post by support is still extant but it may help understand these issues.
I think there are a few misunderstandings that I wish to address here.
I swapped batteries and reset the button for three seconds. The thermostat is showing a spanner symbol. App says it has connected to the server but above continue installation it says device not mounted in red?
Yes, mine is the same. The target temperature for the smart thermostat is 22deg, it reads 26deg, but every so often the boiler switches on and heats the radiators. Not very smart!