If your thermostat is behaving erratically or something strange is in the display, hitting “Reset” buttons can often correct the problem.
Try this first since it does not erase anything. Take the front of the thermostat off the wall and look for a small black round reset button on the left side labeled “HW RST”. Hold this button down for at least 5 seconds. The screen should fully populate temporarily.
You will have to reset the day and time.
If this does not correct the problem, proceed to a Software Reset
These steps will erase your custom program settings, so write down all temperatures and start times before you begin.
Look for a small black round reset button on the right side labeled “SW RST” Hold this button down for at least 5 seconds. The screen should fully populate temporarily.
Place thermostat front cover back on the wall.