Any touch of the screen will wake it up.
The big number on the left is the current temp.
The number on the right is what it is assigned to cool to.
Toggle it to your desired temp with the black arrows.
If it’s cooling and you’d rather heat (or vice versa), find this along the bottom row.
That will take you to this screen where you can change it.
The thermostat for the upstairs region is just outside the Bunk Room.
