How to Test Your Home Thermostat’s Accuracy

How to Test Your Home Thermostat’s Accuracy

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Thermostat accuracy and efficiency is important to the performance of your home’s heating and cooling systems. Many homeowners blindly trust that their thermostats are giving correct readings, but inaccurate thermostats are a common problem. Estes Services shares how you can test your thermostat and what to do to help it perform efficiently throughout the year.

How to Test Your Thermostat for Accuracy and Efficiency

Problems with thermostat accuracy and efficiency can lead to discomfort and energy waste by your heating and cooling systems. Luckily, testing the accuracy of your thermostat readings is fairly easy and can be done without the help of a heating and air conditioner professional.

You’ll need:

  • Tape
  • Soft paper (paper towel or paper napkin)
  • Glass tube thermometer

Steps to test thermostat accuracy and efficiency:

  • Pick a location a few feet away from the thermostat’s location. Make sure this area is not exposed to direct sunlight, near windows or doors, or susceptible to other sources of heat, such as lights.
  • Place the soft paper against the wall, set the thermometer on top of it, and tape it to the wall at the same height as your thermostat. The paper layer prevents the thermometer from detecting heat from the wall. 
  • Leave the thermometer for 20 minutes, then come back and check the temperature on the thermometer and your thermostat.

If both your thermometer and your thermostat display the same temperature reading, the thermostat’s accuracy and efficiency are good. A difference of 3 degrees or less is generally nothing to worry about. If the readings are different, there is likely an issue affecting your thermostat’s function. 

If the difference is minimal yet above 3 degrees, the thermostat may be affected by debris. Try using a soft brush or a can of compressed air to clean the vents on the casing of your thermostat. Remove the cover, and clean contact points of dust and debris. You can also replace the batteries if your thermostat is battery powered. Leave both units in place for another 20 minutes, and check the readings again to see if the readings are the same. 

If the readings between your thermostat and thermometer are still different, you likely have a malfunctioning thermostat and there may be an issue impacting thermostat accuracy and efficiency. 

Correcting Thermostat Issues

If the above experiment shows a problem with thermostat accuracy and efficiency that does not resolve by cleaning the thermostat, it’s time to call your trusted HVAC technician, as you may have a faulty thermostat. Your HVAC professional is able to adjust the thermostat’s calibration so the unit can maintain thermostat accuracy and efficiency through the year. If wiring issues are present, a pro is able to fix these issues or reposition the unit without causing harm to the thermostat or disrupting communications between the thermostat and your heating and cooling units.

Your HVAC technician will also be able to inform you if thermostat accuracy and efficiency is shot and replacement is necessary. If the thermostat cannot be recalibrated to detect temperatures accurately, it is in your best interest to install a new one that will offer accurate readings and communication with your HVAC system so that energy is not wasted. 

Thermostat Installation and Service in Atlanta

If you need help measuring thermostat accuracy and efficiency, give Estes Services a call! Our heating and air conditioning system technicians are happy to assist you and will make sure your current thermostat receives the services needed for accurate temperature monitoring, or we will install a new thermostat to ensure your home maintains the temperatures you desire.