How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat producers, and we proudly install them on a usual basis in Albany. They’re sturdy and trustworthy. In addition, Honeywell is frequently updating its technology, bringing more features for your family.

Nevertheless, every thermostat can experience errors at one time or another. That’s why we’ve put together this informative guidebook to go over troubleshooting. While Honeywell thermostat problems are rare, they happen. 

While you can usually repair the majority of thermostat issues alone, they occasionally need Expert support. Our HVAC Experts are here to assist you when you need us. We’re merely a call away at 518-205-3324.

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

What Kind of Thermostat Do I Have?

There are three models of thermostats:

  • Manual—This is the typical 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 has a digital screen and arrows you press to choose your desired temperature. You can also set daily programs to lower the temperature when you’re at work and increase it when you come home.
  • Smart—You won’t have to make any programs on this thermostat, as it adjusts to your schedule. It automatically changes the temperature when you or other household members are out and about to help you save on utility bills. You can also change the temperature anywhere via your phone or other Wi-Fi-enabled device. 

As you know the majority of technologically advanced products, there are several glitches that might occur. Most of these issues don’t call for pro support and are uncomplicated enough to fix by yourself.

Common Honeywell Thermostat Problems

Each thermostat has a special kind of codes that correspond to the glitches that occur.

Think how simple it can be to fix a computer by restarting it. In most cases, troubleshooting a thermostat can be just as simple.

Here is a guide to the most encountered Honeywell thermostat issues. These include the following programmable thermostats:

Display is Blank

If the display is clear on your programmable thermostat, you might need to install new batteries. If that doesn’t solve the trouble or you rely on a smart thermostat, there may be a wiring problem.

Next, you should check the power is on for your furnace or air handler. Verify the switch close to the indoor unit is in the “on” position.

Additionally, you should confirm all furnace cabinet or air handler doors/panels are securely fastened.

A loose panel may trigger the safety switch, which stops power to the equipment.

Less frequently, an empty display can signify you should install a new thermostat.

HVAC Equipment Won’t Work

Check that your thermostat is set to “cool” or “heat,” not “off.”

In the summer, verify you put the thermostat below the ambient temperature. In the winter, confirm it’s higher. This sounds absurd, but we’ve seen it take place a lot of times.

Ensure the power switch near your indoor unit is in the “on” position. You should also comfirm the cabinet doors or panels are closed on your furnace cabinet or air handler. A loose panel can activate the safety switch, stopping current to the system.

Unit still won’t turn on? Verify circuit breakers haven’t turned off and that your HVAC unit isn’t displaying error codes.

“Cool On” or “Heat On” is Flickering

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

Then, check it’s signaling the appropriate unit to turn on. This is usually demonstrated by “cool on,” “heat on” or an illustration.

If this phrase or the picture is flashing, your thermostat is in a five-minute delay state. This mode stops your system from damaging short cycling. This may occur if you lose power.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump must be serviced. Call D.A. Bennett Service Experts at 518-205-3324 for support.
  • 168—Wi-Fi radio error. Reach Lyric technical support at 800-633-3991. 170—Internal memory error. Call Lyric technical support at 800-633-3991.
  • 171—Set date and time. Finish these settings so scheduling can take place.
  • 173—Thermostat temperature sensor error. Call Lyric technical support at 800-633-3991.
  • 175—AC power restored. No action required.
  • 181/182—Replace air filter. Clear the thermostat by tapping “dismiss” after putting in a clean filter.
  • 184—Install a new humidifier pad. Clear the monitor by hitting “dismiss” after installing a fresh pad filter.
  • 185—Put in a new dehumidifier filter. Clear the display by touching “dismiss” after putting in a fresh filter.
  • 187—Clean or put in a new ventilator filter. Clear the thermostat by tapping “dismiss” after putting in a new filter.
  • 188/189—Install a new UV bulb. Call D.A. Bennett Service Experts at 518-205-3324 for support.
  • 210—Register online for outdoor temperature. Get the Lyric app to complete this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and exterior temperature. Use the Lyric app to finish this step and ensure accurate thermostat operation.
  • 399—No Internet. Check your network settings.
  • 400—No Wi-Fi signal. Wait for the thermostat to reconnect or select new Wi-Fi network.
  • 508—Wi-Fi not set up. Download the Lyric app and follow the procedure to link your thermostat.

For more details, view this thermostat’s user manual.

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump needs service. Contact D.A. Bennett Service Experts at 518-205-3324 for support.
  • 168—Wi-Fi radio error. Call D.A. Bennett Service Experts at 518-205-3324 for support.
  • 170—Internal memory error. Reach D.A. Bennett Service Experts at 518-205-3324 for assistance.
  • 171—Set date and time. Finalize these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Call D.A. Bennett Service Experts at 518-205-3324 for help.
  • 175—AC power resumed. No action needed.
  • 177—Indoor temperature sensor error. Call D.A. Bennett Service Experts at 518-205-3324 for support.
  • 178—Outdoor temperature sensor error. Call D.A. Bennett Service Experts at 518-205-3324 for support.
  • 181/182—Install a new air filter. Clear the screen by touching “dismiss” after installing a clean filter.
  • 183—Rinse humidifier tank and replace water filter. Clear the screen by touching “dismiss” after doing these tasks.
  • 184—Replace humidifier pad. Clear the monitor by hitting “dismiss” after getting a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the screen by tapping “dismiss” after adding a clean filter.
  • 186—Rinse ventilator core. Clear the monitor by touching “dismiss” after doing this task.
  • 187—Rinse or install a new ventilator filter. Clear the monitor by hitting “dismiss” after buying a new filter.
  • 188/189—Get a new UV bulb. Get in touch with D.A. Bennett Service Experts at 518-205-3324 for assistance.
  • 210—Register online for outside temperature. Get the Lyric app to finish this step and ensure correct thermostat operation.
  • 388—Register online for remote access and outdoor temperature. Get the Lyric app to do this step and ensure correct thermostat operation.
  • 399—No Internet. Check your network settings.
  • 400—No Wi-Fi signal. Wait for the thermostat to reconnect or select new Wi-Fi network.
  • 508—Wi-Fi not configured. Use the Lyric app and follow the steps to connect your thermostat.

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

Our Experts are Ready to Provide Assistance

If you’re still having troubles after going through the troubleshooting process, our pros are ready to help. Give us a call at 518-205-3324 and we’ll come to your house rapidly to figure out the malfunction.

If you rely on an aging thermostat, now is a great time to consider a new device. Thermostat technology has come a long way in recent years Ask us for more details on how smart thermostats can make your home more comfortable while helping save on energy expenses throughout the year.

Contact Us