The display has no back lighting. I assume it has to have back lighting or you could only use it during the day. Trouble shooting mentions a weak battery as the problem. Instruction do not mention back lighting.
at all. The filter reminder is not defined how you change the number of hours. I only see some strange character when I attempt to set it. If I remove the battery there is no indication that the battery is low (It is missing). Changing the temperature is harder then it needs to be (press the large button to enter the menu, press the or - multiple times, press the enter button.