If you are seeing the following symbol on the screen:
The thermostat is telling you that you have a low battery.
This is the first stage of the low battery warring.
We suggest that you change batteries as soon as possible.
If you see the letters LO on the screen you are now in the 2nd stage of low battery - Just touch the screen and it will go away.
Again is is best if you change the batteries soon.
If you see the letters LO on the screen and when you press the screen they will not go away. Your are in the last stage of low battery and the unit will shut down very soon. This means you will have no heat or cool. So it is imperative that your change the batteries now.
Please replace with name brand Alkaline Batteries like Duracell, Energizer or Rayovac. Do not use rechargeable batteries.