Thermostat Troubleshoot: Why Is My Thermostat Not Working?

Are you noticing your thermostat acting funky, is it not working, not displaying anything on the screen, or not communicating correctly to your heating and cooling system?

We have come up with a list of items you can look into to determine the problem with a faulty thermostat and some solutions. These solutions will help you determine if the problem is your thermostat or your heating system.

Checking the Thermostat

Here is a list of items to check for your thermostat and hopefully some of these easy fixes will get your thermostat up and working again.

1. Is the power on?

Checking if your thermostat has power should be the first thing you do. Doing this is simple, check the wiring of your thermostat to make sure everything is fitting tightly and appropriately.

2. Check for dust or dirt

Dirty wires can prevent your thermostat from working. Remove the cover of your thermostat and clean the wires of dust. Using a compressed air sprayer will help you with cleaning your wires with care.

3. Check for loose or corroded wires

  • Replace corroded wires
  • Tighten up the loose wires

See if that gets your thermostat to work again.

4. Inconvenient placing of thermostat

The thermostat detects the temperature of the room and compares it to the desired temperature setting. If the room is too warm or too cold, the thermostat requests heat or air depending on the temperature it senses.

Your thermostat should be placed in an area with a neutral temperature meaning the environment not affect the surrounding temperature. The kitchen, for example, would be a bad place to have your thermostat as cooking can make the thermostat read temperatures hotter than what it is due to cooking fumes. Make sure your thermostat is in an area that is well insulated.

5. Make sure thermostat is leveled

Making sure your thermostat is not slanted or tilted might seem like a small detail, but it’s important for your thermostat to be leveled for it to function properly. Your thermostat should be mounted 5 feet from the ground to function properly.

6. Modify by five degrees

  • Set the thermostat five degrees warmer during the heating season
  • Set the thermostat five degrees cooler during the cooling season

Notice the effect this has on your home, check if your heating or cooling system turns on after this.

7. Is your thermostat on the correct “heat” or “cool” setting?

Check the setting on your thermostat and also test the circuit breaker to make sure the switches for your heating and cooling unit is set to “ON.”

If your issue is that your air conditioner or furnace is blowing air always, your thermostat’s fan setting may be set to ON.

It should be set to AUTO, which means the blower will only blow air out the vents when the air conditioning or furnace cools and heats the air respectively.

This is where you should start in your attempt to troubleshoot your thermostat.

Frequently Asked Questions (FAQs): Thermostats

Why is my thermostat’s display blank?

  • Replace the batteries (see the next question if this does not work)
  • Flip the AC/Furnace switch on your circuit breaker to OFF then back ON
  • Reset the thermostat – this can be done by flipping the switch from OFF and Heat continuously

Why is my thermostat not working after changing batteries?

  • Check to see if the batteries were placed correctly
  • Check the voltage of your thermostat
  • Check the breaker, tripped breakers are common reason for why the thermostat is not working

If after checking the above, consider replacing the thermostat, the thermostat could simply be bad, you can buy a replacement thermostat at any home improvement store.

I can hear the fan running, but my thermostat still won’t work

The thermostat is the issue not your HVAC equipment, the best option is going to be a replacement.

My heating, cooling, or fan runs constantly

  • Before doing anything turn off your heating or cooling unit
  • Check connections to make sure nothing has short circuited
  • Set “Fan” to “AUTO” – Fan ON will mean the fan will constantly run, Fan AUTO means the fan will work in accordance to your heating and cooling settings

Thermostat is not working after power outage

  • Try toggling the switch from Fan to Electric on and off

We hope that covers some issues you have about your thermostat. Call One Hour Heating & Air Conditioning® of the Bay Area for a better walkthrough of your home’s heating and cooling adjustments. If your thermostat is the issue, we can have it replaced, or repaired.

The issue may not be your thermostat at all and could likely be a mechanical problem with your heating, ventilation, and cooling unit. Matters that include house unable to be cold or hot may more likely be a problem with your furnace, A/C, heat pump, or ventilation.

One Hour Heating & Air Conditioning® of the Bay Area is a simple phone call away.