How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat manufacturers, and we proudly install them on a regular basis in Jacksonville. They’re durable and trustworthy. Also, Honeywell is constantly advancing its technology, offering more features for your home.

Nevertheless, all thermostats can have problems every so often. As a result, we’ve compiled this helpful guide to run through troubleshooting.

While you can usually fix the majority of thermostat issues on your own, they occasionally require Expert help. Our heating and cooling professionals are ready to support you when you need us. We’re just a call away at 904-450-5672.

Let’s start the process by figuring out what model of thermostat your house has.

What Kind of Thermostat Do I Have?

There are three types 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 reducing energy costs.
  • Programmable—This thermostat includes a digital screen and arrows you use to choose your desired temperature. You can also set daily programs to decrease the temperature when you’re away and increase it when you get back.
  • Smart—You won’t have to schedule any programs on this thermostat, as it learns your schedule. It instinctively adjusts the temperature when you or family members are gone to help you save on heating and cooling bills. You can also adjust the temperature anywhere using your phone or other Wi-Fi-enabled device. 

As you’re aware most technologically advanced products, there are regular malfunctions that might take place. Many of these troubles don’t need pro support and are uncomplicated enough to solve by yourself.

Common Honeywell Thermostat Problems

All thermostats have a special set of codes that correspond to the glitches that take place.

Think how uncomplicated it can be to repair a computer by restarting it. In most cases, diagnosing a thermostat can be just as simple.

Here are some of the most common Honeywell thermostat issues. These include the following programmable thermostats:

Display is Blank

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

Next, you should make sure the power is enabled for your furnace or air handler. Make sure the switch by the indoor unit is switched “on”.

In addition to that, you should make certain all furnace cabinet or air handler doors/panels are sturdily secured.

An unsecured panel may trip the safety switch, which cuts off power to the equipment.

While it’s less common, an empty monitor might mean you should get a new thermostat.

Comfort Equipment Won’t Work

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

In the summer, make sure you schedule the thermostat below the room temperature. In the winter, verify it’s higher. This sounds goofy, but we’ve seen it occur a lot of times.

Ensure the power switch close to your indoor system 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 trigger the safety switch, stopping electricity to the equipment.

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

“Cool On” or “Heat On” is Blinking

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

Then, verify it’s calling for the right equipment to run. This is typically demonstrated by “cool on,” “heat on” or an illustration.

If these words or the icon is blinking, your thermostat is in a five-minute delay status. This feature protects your system from harmful short cycling. This could occur if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump requires service. Call Air Engineers Service Experts at 904-450-5672 for assistance.
  • 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 occur.
  • 173—Thermostat temperature sensor error. Contact Lyric technical support at 800-633-3991.
  • 175—AC power restarted. No action needed.
  • 181/182—Put in a new air filter. Clear the thermostat by touching “dismiss” after installing a new filter.
  • 184—Install a new humidifier pad. Clear the display by touching “dismiss” after putting in a fresh pad filter.
  • 185—Install a new dehumidifier filter. Clear the screen by hitting “dismiss” after putting in a clean filter.
  • 187—Wash or install a new ventilator filter. Clear the monitor by touching “dismiss” after installing a new filter.
  • 188/189—Install a new UV bulb. Contact Air Engineers Service Experts at 904-450-5672 for support.
  • 210—Register online for exterior temperature. Get the Lyric app to do this step and ensure correct thermostat operation.
  • 388—Register online for remote access and exterior temperature. Use the Lyric app to finish this step and ensure correct thermostat operation.
  • 399—No Internet. Confirm 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 procedure to configure your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump needs service. Contact Air Engineers Service Experts at 904-450-5672 for assistance.
  • 168—Wi-Fi radio error. Contact Air Engineers Service Experts at 904-450-5672 for help.
  • 170—Internal memory error. Reach Air Engineers Service Experts at 904-450-5672 for support.
  • 171—Set date and time. Finalize these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Contact Air Engineers Service Experts at 904-450-5672 for support.
  • 175—AC power resumed. No action needed.
  • 177—Indoor temperature sensor error. Call Air Engineers Service Experts at 904-450-5672 for support.
  • 178—Outdoor temperature sensor error. Contact Air Engineers Service Experts at 904-450-5672 for help.
  • 181/182—Get a new air filter. Clear the monitor by tapping “dismiss” after adding a clean filter.
  • 183—Clean humidifier tank and replace water filter. Clear the monitor by tapping “dismiss” after completing these steps.
  • 184—Replace humidifier pad. Clear the display by touching “dismiss” after installing pad filter.
  • 185—Get a new dehumidifier filter. Clear the monitor by hitting “dismiss” after putting in a new filter.
  • 186—Rinse ventilator core. Clear the display by touching “dismiss” after completing this task.
  • 187—Rinse or install a new ventilator filter. Clear the monitor by touching “dismiss” after getting a new filter.
  • 188/189—Replace UV bulb. Contact Air Engineers Service Experts at 904-450-5672 for help.
  • 210—Register online for outdoor temperature. Use the Lyric app to complete this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and outdoor temperature. Get the Lyric app to finish this step and ensure proper thermostat operation.
  • 399—No Internet. Confirm your network settings.
  • 400—No Wi-Fi signal. Wait for the thermostat to reconnect or select new Wi-Fi network.
  • 508—Wi-Fi not connected. Download the Lyric app and follow the process to connect your thermostat.

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

Our Experts are Here to Provide Assistance

If you’re still experiencing troubles after working through the troubleshooting steps, our professionals are available to support you. Give us a call at 904-450-5672 and we’ll arrive quickly to determine the issue.

If you have an older thermostat, now is a good time to consider a new thermostat. Thermostat technology has gotten better lately Ask us for more information on how smart thermostats can make your residence better while helping save on utility costs all year.

Contact Us