I had an Emerson 1E78-140 thermostat installed about a year ago. This morning, it was set to 68°F, but the thermostat is showing the room temperature as 65°F. The room does not feel chilly at all, so I believe the actual temperature is closer to 68°F.

For context, the outdoor temperature this morning is –1°F. The battery indicator on the thermostat is not showing low, so I don’t suspect a battery issue.

My home has a zoned system, and this thermostat controls only one room (approximately 18 × 22 ft). The system appeared to be running continuously in an attempt to reach 68°F and was not shutting off. I power-cycled the thermostat, but the display still shows 65°F.

When I checked the furnace, Zone 3 still shows as active, even though the thermostat reading hasn’t changed.

Has anyone experienced something similar with this model?