How to Troubleshoot a Digital House Thermostat

Digital thermostats commonly include LCD display screens and push-button controls. Modern digital units are distinguishable from traditional mechanical and clock-based thermostats, which use moving arrows and levers to show and change household temperature, respectively. However, digital thermostats can be broken down into even more advanced, high-tech categories, such as programmable digital units. Some digital thermostats even alert households when it is time to change the filter. Troubleshooting digital thermostats can be dependent on the brand and model in your home. Nonetheless, you can perform at least four general troubleshooting steps on the digital thermostats found in many in homes today.

Digital thermostat and remote control
credit: Ryan McVay/Photodisc/Getty Images
You may need to troubleshoot interference for a remote-controlled thermostat.

Step 1

Check the system switch for the correct temperature setting. To produce heat, raise the temperature to a degree value higher than the actual room temperature shown on many digital thermostat display screens. To cool the home, lower the temperature to a setting below the current room temperature. Whether heating or cooling the home, give the system a minimum of five minutes to make the temperature adjustment.

Step 2

Replace the batteries in the thermostat unit if the display does not light up. Most manufacturers use common household battery sizes, such as AAA and AA. Look in the owner's manual to see if another battery size is necessary for your thermostat, such as button batteries. Make sure the ends of the battery are aligned with the respective positive (+) and negative (-) connections in the battery slot. You may have to perform a hard reset on the thermostat by pressing the "Reset" or similarly labeled function.

Step 3

Confirm that electrical power is running to the heating and cooling system. At your home's circuit breaker or fuse box, switch the breaker back to "On" or replace a blown fuse. Though the thermostat's digital display might be powered by battery, the home's heating, ventilation and air conditioning system runs off electrical power.

Step 4

Verify that the time is properly configured on a programmable digital thermostat if it is not heating or cooling as desired. Make sure that the clock is set to use "A.M." during the day and "P.M." during the evening. Also, ensure the programmable thermostat is not in a type of override mode or similar state. Having the ability to manually adjust the temperature will prevent the thermostat from automatically carrying out programmed settings.