How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the best thermostat brands, and we proudly install them on a frequent basis in Haltom City. They’re long-lasting and trustworthy. Plus, Honeywell is regularly enhancing its technology, resulting in more features for your home.

Still, all thermostats can run into issues now and then. That’s why we’ve compiled this valuable guidebook to walk you through troubleshooting.

While you can typically solve the majority of thermostat problems alone, they sometimes call for Expert support. Our home comfort Experts are ready to support you when you need us. We’re only a call away at 817-668-6689.

Let’s get started with the process by finding out what model of thermostat your residence has.

What Kind of Thermostat Do I Have?

There are three types of thermostats:

  • Manual—This is the typical dial-shaped thermostat. You won’t run into error codes with this type, but it’s also the least efficient for saving on heating and cooling expenses.
  • Programmable—This thermostat includes a digital screen and arrows you use to set your desired temperature. You can also choose daily programs to decrease the temperature when you’re away and raise it when you come home.
  • Smart—You won’t have to schedule any programs on this thermostat, because it picks up on your schedule. It automatically changes the temperature when you or family members are away to help you save on utility expenses. You can also raise or lower the temperature anywhere using your phone or other Wi-Fi-enabled device. 

As you know many technologically advanced products, there are common glitches that might take place. Many of these problems don’t need pro assistance and are uncomplicated enough to solve by yourself.

Common Honeywell Thermostat Problems

Each thermostat has a special set of codes that correspond to the issues that take place.

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

Here is a listing the most reported Honeywell thermostat issues. These apply to the following programmable thermostats:

Display is Blank

If the screen is blank on your programmable thermostat, you may need to install new batteries. If that doesn’t take care of the problem or you use a smart thermostat, there may be a wiring issue.

Next, you should check the power is flowing for your furnace or air handler. Confirm the switch by the indoor unit is switched “up”.

In addition to that, you should confirm all furnace cabinet or air handler doors/panels are tightly secured.

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

Infrequently, an empty screen can signify you need to buy a new thermostat.

HVAC Equipment Won’t Run

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

In the summer, make sure you schedule the thermostat lower than the room temperature. When it’s cool, verify it’s higher. This sounds absurd, but we’ve seen it occur a lot of times.

Make sure the power switch close to your indoor equipment is in the “on” position. You should also check the cabinet doors or panels are tight on your furnace cabinet or air handler. An open panel can trip the safety switch, diverting power to the system.

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

“Cool On” or “Heat On” is Blinking

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

Then, check it’s telling the appropriate equipment to turn on. This is typically demonstrated by “cool on,” “heat on” or an icon.

If this set of words or the illustration is blinking, your thermostat is in a five-minute delay mode. This feature protects your unit from damaging short cycling. This may take place if you lose power.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump requires service. Call Stark Services at 817-668-6689 for support.
  • 168—Wi-Fi radio error. Call Lyric technical support at 800-633-3991. 170—Internal memory error. Call Lyric technical support at 800-633-3991.
  • 171—Set date and time. Finalize 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—Put in a new air filter. Clear the screen by hitting “dismiss” after adding a clean filter.
  • 184—Install a new humidifier pad. Clear the display by hitting “dismiss” after installing a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the monitor by tapping “dismiss” after adding a clean filter.
  • 187—Clean or install a new ventilator filter. Clear the screen by tapping “dismiss” after installing a new filter.
  • 188/189—Get a new UV bulb. Call Stark Services at 817-668-6689 for support.
  • 210—Register online for outside temperature. Use the Lyric app to finish this step and ensure proper thermostat operation.
  • 388—Register online for remote access and outside temperature. Download 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 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 information, see this thermostat’s user manual.

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump requires service. Reach Stark Services at 817-668-6689 for help.
  • 168—Wi-Fi radio error. Reach Stark Services at 817-668-6689 for assistance.
  • 170—Internal memory error. Contact Stark Services at 817-668-6689 for assistance.
  • 171—Set date and time. Finalize these settings so scheduling can operate.
  • 173—Thermostat temperature sensor error. Contact Stark Services at 817-668-6689 for support.
  • 175—AC power resumed. No action needed.
  • 177—Indoor temperature sensor error. Reach Stark Services at 817-668-6689 for assistance.
  • 178—Outdoor temperature sensor error. Contact Stark Services at 817-668-6689 for help.
  • 181/182—Get a new air filter. Clear the monitor by hitting “dismiss” after adding a clean filter.
  • 183—Rinse humidifier tank and replace water filter. Clear the thermostat by touching “dismiss” after finishing these tasks.
  • 184—Replace humidifier pad. Clear the screen by tapping “dismiss” after installing pad filter.
  • 185—Replace dehumidifier filter. Clear the monitor by tapping “dismiss” after putting in a clean filter.
  • 186—Wash ventilator core. Clear the display by touching “dismiss” after finishing this task.
  • 187—Rinse or install a new ventilator filter. Clear the monitor by touching “dismiss” after buying a new filter.
  • 188/189—Replace UV bulb. Get in touch with Stark Services at 817-668-6689 for assistance.
  • 210—Register online for outside temperature. Get the Lyric app to complete this step and ensure correct thermostat operation.
  • 388—Register online for remote access and outside temperature. Get the Lyric app to complete this step and ensure proper 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 configured. Get the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Available to Help

If you’re still having problems after going through the troubleshooting list, our professionals are available to help. Call us at 817-668-6689 and we’ll arrive as fast as we can to determine the problem.

If you rely on a dated thermostat, now is a great 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 comfier while helping save on heating and cooling expenses all year.

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