Your Honeywell thermostat might not switch on the air conditioning. Resetting your thermostat is the modest way out. Changing your batteries, inspecting your wiring, and cleaning the air filter connected to your Honeywell Thermostat are additional popular solutions.

How do you troubleshoot your Honeywell thermostat?

  1. Set your thermostat to match your air conditioner

Your air conditioner might not turn on if your Honeywell thermostat is not configured to function with your heating and cooling systems. If your thermostat was turning on your AC and then unexpectedly stopped, your HVAC system may be no longer compatible with the settings on your thermostat. Most likely as a result of the development of your HVAC system. As a result, you must modify the thermostat on your HVAC system to see if the problem has been resolved. To alter the settings on your Honeywell thermostat, attempt these steps:Select the System button on your Honeywell thermostat. An empty box will appear as a result. Keep pressing the empty box until your Honeywell thermostat’s screen changes and displays your Model ID. Most Honeywell thermostats have a Model ID that starts with TH or RH and ends with digits. After that, choose Menu from the menu. Next, choose Installer. The computer will ask you to enter your date code. The back of your Honeywell thermostat is where you’ll find the date code. Your Honeywell thermostat will show your installation settings if you’ve supplied the right date code. Press and hold the FAN and UP navigation buttons at this juncture. The thermostat will show Setting Number 0 and Function Number 1 respectively. The settings for the different types of heating and cooling systems are covered by function number 1.

Click Done to leave the installation settings after determining the best option for your AC.

Continue to the following troubleshooting step if this is ineffective.

  1. Activate the cooling feature on your Honeywell thermostat by pressing the appropriate button.

No matter what you do, your Honeywell thermostat won’t turn on your air conditioner even if it’s properly configured. Then, check to see if your thermostat’s cooling mode has been set. Only if the cooling mode on your Honeywell thermostat is turned on will it be able to switch your AC on automatically.

Check to see if “COOL ON” is shown on the screen of your Honeywell thermostat to see whether it is in cool mode. If not, you must set the thermostat to cooling mode.

This is how to accomplish it:

Locate the Heat Off/Cool system slider switch on your thermostat. Change the switch’s setting to “Cool. ”The temperature can then be adjusted to the desired level using the on-screen arrows. Your Honeywell thermostat’s cooling mode is now turned on.

  1. Attach the RC terminal to your RC wire.

The body of your Honeywell thermostat contains a wire with the designation RC (Red Cooling). Your home’s cooling system is powered by this line (Fan and AC). Nevertheless, the RC must be connected to the RC terminal to work. After turning on your Honeywell thermostat, if your air conditioner doesn’t turn on, your RC cable may not be attached to its terminal. You must reattach your RC wire to the RC system to resolve this problem. By removing the Honeywell thermostat’s cover, you can see the RC wire and terminal. Ask a professional for assistance if you are unsure how to tackle electrical problems.

  1. Clear out the air vents

After turning on your furnace, if you still have trouble getting cold air into your room, you may need to clean your air vents. Your home’s rooms are heated and cooled by air that is circulated through your air vents. But if the vents are obstructed, air may not be able to flow through them. When dirt builds up on their surfaces, air vents become clogged. Air will circulate more abundantly in the home’s rooms if your air vents are cleaned. By washing the covers of your air vents with soap and water, you may clean them.

  1. Finally, replace the batteries.

A low battery in your Honeywell thermostat may prevent your air conditioner from turning on. Because of this, you will need to buy fresh batteries. Your Honeywell thermostat’s battery life can be gleaned from its display screen. If the battery is bad, it will show up on the screen as “No power source.” If you see this message, it’s time to change the Honeywell thermostat battery. To change the thermostat’s battery, follow these steps:

The thermostat should be removed from the wall. Using a screwdriver, remove the batteries from the side of your thermostat. Remove the old batteries from the battery box and replace them with new ones. ‘After closing the compartment, reinstall your Honeywell thermostat on the wall.

You should reset your Honeywell thermostat to its factory settings.

Once you’ve tried all of the troubleshooting methods outlined above, reset your thermostat if your AC still doesn’t work. Your thermostat’s reset protocol may differ based on its model ID. When looking for the Model ID, you’ll want to remove the thermostat from the wall. Your model ID is made up of the numbers following the letters RHT, CT, TH, RLV, TL, CT, or T. With the model ID now in hand, it’s time to start the reset process.

Conclusion

So, that’s how to go about fixing a Honeywell thermostat that won’t start the air conditioning. Try contacting Honeywell support to seek help even after you’ve tried all the troubleshooting techniques in this article, or get an HVAC professional to examine the thermostat on your behalf.