Why does my system run with setpoint and room temperature the same?
In cooling, as the room temperature falls you will eventually reach the setpoint temperature. The system will continue to run until it reaches the low side of the temperature setting. As an example: If set to 78 degrees with the room temperature falling the thermostat will continue to call for cool as the temperature decreases in the following manner. 78.9, 78.8, 78.7, 78.6, 78.5, 78.4, 78.3, 78.2. At approximately 78.2 the thermostat will quit calling for cool. This is why it is not unusual for the room temperature and set temperature to read the same but the system continues to run. The amount of time it takes for the system to shut off is dependent on system sizing, thermostat location, etc. Note: The thermostat display only displays whole numbers. Internally the thermostat calculates decimals. In heating as the room temperature increases the system will continue to run until the thermostat reaches the high side of the temperature setpoint.