I am getting a lot of warnings by .comfoair.handling.ComfoAirConnector .
How can I turn this off?
Setting it to INFO, WARN doesn’t help.
Set it to ERROR 
I was more thinking of somewhat like /dev/null
But you are using the binding?
It’s no good not to see if any errors occured. If not using the binding, remove it from ./addons/
If a binding is too chatty when logging is set to INFO and WARN, then it possibly should be looked at to make it useful at that level. Maybe some information should be reduced to DEBUG…
Logging should be useful, and it probably shouldn’t be completely disabled otherwise how do you know when something goes wrong, what happened, and when?
If you’re worried about it filling up the disk, you can also look to change the rotation policy in the logback.xml (in OH1 this is easy - I’m not sure about OH2). This sets how many files you keep, how often they change name, what size etc…