THERMOSTAT BLANK or THERMOSTAT DOESN’T WORK– The display on a digital thermostat shows no information or the thermostat does not function properly.
POSSIBLE PROBLEM & DESCRIPTION
Most digital thermostats require batteries. Try replacing the thermostat batteries and see if the display returns. Watch Video.
No Furnace Power
Some digital thermostats will lose the display if there is no power from the furnace or air handler. Check power sources. If there is still no display, you should have a qualified technician diagnose.
No display may just be caused by a bad thermostat. If there are good batteries and the thermostat is receiving power from the furnace or air handler, but there is still no display – it is likely a bad thermostat.