How to Troubleshoot Your Thermostat for Basic Issues

May 28, 2021
0 minute read

Even if every other part of your HVAC system is working just fine, if there’s something wrong with your thermostat, you’re going to have heating and cooling issues. Before calling a technician, here are some troubleshooting tips to help you identify and solve what’s wrong with your thermostat.


1. If your thermostat is still responding, check the settings.

Even if you’re pretty sure you know your thermostat’s settings, trust us: it always pays to double-check, especially if there are other people in the house who may have adjusted them.

  • Typically, you want your thermostat to be set on “Auto” so that your system will heat or cool your home according to your designated preferences. If your thermostat is set to “On,” this means that your system's fan is going to run continuously, even when your system is neither heating nor cooling the air.
  • Next, check your preferences. Are your AC and heater set to come on at your preferred temperatures? Adjust as needed.


2. If your thermostat is still responding, check its Wi-Fi connection.

Newer digital thermostats often rely on a Wi-Fi connection to receive bug fixes and updates. Occasionally, a thermostat can become disconnected from your home’s Wi-Fi. This may happen following a momentary power outage.


If your thermostat is not getting updates while being connected to Wi-Fi, and if you notice that your Wi-Fi connection seems particularly spotty and slow on your other devices, try resetting your router.


3. If your thermostat is NOT responding, check the power source.

Thermostats can be powered by batteries, hardwired, or hardwired while containing a backup battery. If your thermostat contains batteries and won’t respond, replacing the batteries will most likely solve the issue.


If your thermostat is hardwired, there are a few reasons why it might not be responding:

  • It’s in the middle of recharging. In this case, the blank screen is just temporary, and the display will return shortly.
  • Something tripped the circuit that the thermostat is on, cutting off power to the device. Check to see if the circuit breaker switch needs to be reset or if a fuse needs to be replaced.
  • There’s a problem with the wiring. Wiring can be affected by the settling of a house, old age, and pest activity. Unfortunately, you may not be able to identify this problem just by looking because wiring is inside your walls.


4. If your thermostat still won’t respond, open and close your furnace door.

Occasionally, some furnaces are extremely sensitive to the way the furnace door is shut. If it’s not closed securely, the thermostat will shut off and won’t respond. Before calling a technician, open your furnace door and then try to close it as snugly as you can to see if that fixes the issue.


I’ve tried all this. Now what?

If none of these steps have solved the problem, your thermostat might need to be repaired or replaced. Just like any device, thermostats are susceptible to mechanical problems and old age. If you’re having trouble with your thermostat, don’t hesitate to contact our HVAC professionals at Tom's Mechanical, Inc. for a practical solution:(972) 388-3669.

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