How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the best thermostat producers, and we proudly install them on a frequent basis in the U.S.. They’re sturdy and dependable. Plus, Honeywell is frequently enhancing its technology, resulting in more features for your home.

Nevertheless, all thermostats can experience issues at times. That’s why we’ve compiled this helpful handbook to walk you through troubleshooting. While Honeywell thermostat troubleshooting problems are rare, they do pop up.

While you can often repair the majority of thermostat troubles alone, they occasionally require Expert assistance. Our HVAC pros are here to help when you need us. We’re just a call away at 866-397-3787.

Let’s start the process by finding out what type of thermostat your house has.

What Model of Thermostat Do I Have?

There are three kinds of thermostats:

    • Manual—This is the older dial-shaped thermostat. You won’t experience error codes with this one, but it’s also the least efficient for saving on heating and cooling bills.
    • Programmable—This thermostat features a digital screen and arrows you use to set your desired temperature. You can also use daily programs to decrease the temperature when you’re away and raise it when you come home.
    • Smart—You won’t have to set any programs on this thermostat, since it adjusts to your schedule. It instinctively raises and lowers the temperature when you or other household members are gone to help you save on utility costs. You can also change the temperature anywhere using your phone or other Wi-Fi-enabled device.

As you’re aware many technologically advanced things, there are regular problems that may take place. Many of these troubles don’t need pro assistance and are uncomplicated enough to repair alone.

Common Honeywell Thermostat Troubleshooting Errors

Each Honeywell thermostat has an exclusive kind of codes that correspond to the problems that occur.

Think how simple it can be to repair a computer by restarting it. In many instances, correcting a thermostat can be just as uncomplicated.

Here is a listing the most encountered Honeywell thermostat issues. These involve the following programmable thermostats:

Display is Blank

If the display is empty on your programmable thermostat, you may need to get new batteries. If that doesn’t fix the trouble or you have a smart thermostat, there could be a wiring malfunction.

Next, you should ensure the power is on for your furnace or air handler. Make sure the switch by the indoor system is in the “on” position.

Additionally, you should confirm all furnace cabinet or air handler doors/panels are sturdily in place.

A panel that isn’t tight may trigger the safety switch, which cuts off power to the equipment.

While it’s less common, an empty display might signify you should install a new thermostat.

HVAC Unit Won’t Work

Ensure that your thermostat is on “cool” or “heat,” not “off.”

During warm weather, make sure you set the thermostat lower than the room temperature. In the winter, make sure it’s higher. This sounds absurd, but we’ve seen it happen lots of times.

Ensure the power switch by your indoor equipment is in the “on” position. You should also make sure the cabinet doors or panels are secure on your furnace cabinet or air handler. An open panel can activate the safety switch, diverting electricity to the system.

System still won’t start? Confirm circuit breakers haven’t flipped and that your HVAC system isn’t showing error codes.

“Cool On” or “Heat On” is Flashing

To start, make sure your thermostat is on “cool” or “heat.”

Then, check it’s telling the appropriate equipment to start. This is usually demonstrated by “cool on,” “heat on” or a picture.

If this set of words or the illustration is pulsing, your thermostat is in a five-minute delay status. This setting protects your system from damaging short cycling. This may happen if you lose power.

Honeywell Thermostat-Specific Error Codes

Honeywell Lyric™ T5 Wi-Fi (RCHT8612WF/RCHT9510WFW)

    • 164—Heat pump needs service. Call Service Experts Heating, Air Conditioning & Plumbing at 866-397-3787 for assistance.
    • 168—Wi-Fi radio error. Call Lyric technical support at 800-633-3991. 170—Internal memory error. Reach Lyric technical support at 800-633-3991.
    • 171—Set date and time. Finish these settings so scheduling can run.
    • 173—Thermostat temperature sensor error. Call Lyric technical support at 800-633-3991.
    • 175—AC power resumed. No action required.
    • 181/182—Install a new air filter. Clear the thermostat by tapping “dismiss” after adding a clean filter.
    • 184—Install a new humidifier pad. Clear the display by tapping “dismiss” after adding a clean pad filter.
    • 185—Replace dehumidifier filter. Clear the display by tapping “dismiss” after adding a new filter.
    • 187—Wash or put in a new ventilator filter. Clear the display by hitting “dismiss” after installing a clean filter.
    • 188/189—Get a new UV bulb. Ring Service Experts Heating, Air Conditioning & Plumbing at 866-397-3787 for support.
    • 210—Register online for outside temperature. Download the Lyric app to finish this step and ensure correct thermostat operation.
    • 388—Register online for remote access and outdoor temperature. Use the Lyric app to finish this step and ensure proper thermostat operation.
    • 399—No Internet. Check your network settings.
    • 400—No Wi-Fi signal. Wait for the thermostat to reconnect or pick new Wi-Fi network.
    • 508—Wi-Fi not configured. Use the Lyric app and follow the steps to configure your thermostat.

For more information, see this thermostat’s user manual.

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005)

    • 164—Heat pump needs service. Contact Service Experts Heating, Air Conditioning & Plumbing at 866-397-3787 for support.
    • 168—Wi-Fi radio error. Reach Service Experts Heating, Air Conditioning & Plumbing at 866-397-3787 for help.
    • 170—Internal memory error. Call Service Experts Heating, Air Conditioning & Plumbing at 866-397-3787 for help.
    • 171—Set date and time. Finalize these settings so scheduling can run.
    • 173—Thermostat temperature sensor error. Contact Service Experts Heating, Air Conditioning & Plumbing at 866-397-3787 for support.
    • 175—AC power reconnected. No action needed.
    • 177—Indoor temperature sensor error. Contact Service Experts Heating, Air Conditioning & Plumbing at 866-397-3787 for assistance.
    • 178—Outdoor temperature sensor error. Reach Service Experts Heating, Air Conditioning & Plumbing at 866-397-3787 for help.
    • 181/182—Replace air filter. Clear the screen by hitting “dismiss” after putting in a fresh filter.
    • 183—Wash humidifier tank and replace water filter. Clear the thermostat by touching “dismiss” after completing these tasks.
    • 184—Install a new humidifier pad. Clear the screen by hitting “dismiss” after installing pad filter.
    • 185—Get a new dehumidifier filter. Clear the screen by tapping “dismiss” after adding a fresh filter.
    • 186—Wash ventilator core. Clear the screen by tapping “dismiss” after completing this task.
    • 187—Rinse or replace ventilator filter. Clear the monitor by hitting “dismiss” after installing a new filter.
    • 188/189—Get a new UV bulb. Get in touch with Service Experts Heating, Air Conditioning & Plumbing at 866-397-3787 for support.
    • 210—Register online for outside temperature. Get the Lyric app to do this step and ensure correct thermostat operation.
    • 388—Register online for remote access and exterior temperature. Get the Lyric app to finish this step and ensure correct thermostat operation.
    • 399—No Internet. Verify your network settings.
    • 400—No Wi-Fi signal. Wait for the thermostat to reconnect or pick new Wi-Fi network.
    • 508—Wi-Fi not set up. Download the Lyric app and follow the procedures to connect your thermostat.

For more details, look at this thermostat’s user manual.

Our Experts are Ready to Provide Support

If you’re still running into issues after working through the troubleshooting steps, our professionals are here to help. Call us at 866-397-3787 and we’ll be out as fast as we can to figure out the malfunction.

If you rely on a dated thermostat, right now is a great time to think about a new thermostat. Thermostat technology has come a long way lately Ask us for more info on how smart thermostats can make your residence more comfortable while helping save on heating and cooling costs throughout the year.

Savings For You

See All Offers Here >
Offer

MAKE NO PAYMENTS FOR 30 DAYS!

  • Upgrade to Worry-Free Comfort with the Advantage Program and make NO payments for 30 days!
print
Offer

$50 OFF ANY REPAIR

  • Save $50 on a Paid Service
  • Written 100% Satisfaction Guarantee
  • Plus, ask how to save an additional 15% and waive your trip charge!
print

© 2024 Service Experts, Service Experts Heating & Air Conditioning, and the Service Experts logo and design are registered trademarks of Service Experts LLC and used under license by SE Canada Inc. All Rights Reserved. *Not applicable to the Advantage Program. See your signed Advantage Program Agreement for full details and exclusions. 100% Satisfaction Guarantee is subject to certain restrictions and limitations as set forth in the applicable Terms and Conditions.