How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat brands, and we proudly install them on a usual basis in Saint Charles. They’re long-lasting and reliable. Also, Honeywell is regularly improving its technology, bringing more features for your family.

Nevertheless, every thermostat can have issues every now and then. That’s why we’ve prepared this helpful guidebook to go over troubleshooting.

While you can usually fix the majority of thermostat problems on your own, they occasionally require Expert assistance. Our home comfort Experts are ready to help when you need us. We’re only a call away at 630-246-2698.

Let’s get started with the process by finding out what type 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 have error codes with this one, but it’s also the least efficient for saving on utility expenses.
  • Programmable—This thermostat includes a digital screen and arrows you touch to choose your desired temperature. You can also set daily programs to lower the temperature when you’re gone and increase it when you get back.
  • Smart—You won’t have to make any programs on this thermostat, because it adjusts to your routine. It automatically raises and lowers the temperature when you or other household members are out and about to help you save on energy costs. You can also change the temperature anywhere via your phone or other Wi-Fi-enabled device. 

As you know many technologically advanced things, there are regular malfunctions that might occur. Most of these situations don’t call for Expert assistance and are easy to repair by yourself.

Common Honeywell Thermostat Problems

Every thermostat has a unique kind of codes that correspond to the troubles that occur.

Think how uncomplicated it can be to fix a computer by restarting it. For the most part, diagnosing a thermostat can be just as easy.

Here is a listing the most encountered Honeywell thermostat errors. These are applicable 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 have a smart thermostat, there may be a wiring issue.

Next, you should check the power is flowing for your furnace or air handler. Make sure the switch near the indoor unit is switched “on”.

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

A panel that isn’t tight may activate the safety switch, which disconnects power to the equipment.

While it’s less common, an empty display might signify you will need to get a new thermostat.

Heating and Cooling System Won’t Turn On

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

During warm weather, make sure you schedule the thermostat lower than the ambient temperature. When it’s cool, make sure it’s higher. This sounds goofy, but we’ve seen it occur lots of times.

Confirm the power switch close to your indoor unit is in the “on” position. You should also comfirm the cabinet doors or panels are secure on your furnace cabinet or air handler. An open panel can trip the safety switch, stopping power to the equipment.

Unit still won’t run? Verify circuit breakers haven’t flipped and that your HVAC system isn’t experiencing error codes.

“Cool On” or “Heat On” is Flickering

To begin, make sure your thermostat is switched to “cool” or “heat.”

Then, make sure it’s signaling the right unit to start. This is typically indicated by “cool on,” “heat on” or an illustration.

If this set of words or the icon is flashing, your thermostat is in a five-minute delay state. This setting protects your equipment from bad short cycling. This may occur if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump needs service. Call Golden Seal Service Experts at 630-246-2698 for help.
  • 168—Wi-Fi radio error. Contact Lyric technical support at 800-633-3991. 170—Internal memory error. Contact Lyric technical support at 800-633-3991.
  • 171—Set date and time. Finalize these settings so scheduling can take place.
  • 173—Thermostat temperature sensor error. Reach Lyric technical support at 800-633-3991.
  • 175—AC power restored. No action needed.
  • 181/182—Put in a new air filter. Clear the screen by hitting “dismiss” after installing a new filter.
  • 184—Put in a new humidifier pad. Clear the screen by touching “dismiss” after installing a new pad filter.
  • 185—Put in a new dehumidifier filter. Clear the display by tapping “dismiss” after putting in a clean filter.
  • 187—Wash or install a new ventilator filter. Clear the thermostat by tapping “dismiss” after adding a new filter.
  • 188/189—Install a new UV bulb. Ring Golden Seal Service Experts at 630-246-2698 for support.
  • 210—Register online for outside temperature. Use the Lyric app to complete this step and ensure proper thermostat operation.
  • 388—Register online for remote access and outside temperature. Use the Lyric app to finish 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 choose new Wi-Fi network.
  • 508—Wi-Fi not set. Get the Lyric app and follow the steps to configure your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump must be serviced service. Call Golden Seal Service Experts at 630-246-2698 for support.
  • 168—Wi-Fi radio error. Contact Golden Seal Service Experts at 630-246-2698 for assistance.
  • 170—Internal memory error. Call Golden Seal Service Experts at 630-246-2698 for assistance.
  • 171—Set date and time. Finalize these settings so scheduling can operate.
  • 173—Thermostat temperature sensor error. Call Golden Seal Service Experts at 630-246-2698 for support.
  • 175—AC power restored. No action required.
  • 177—Indoor temperature sensor error. Contact Golden Seal Service Experts at 630-246-2698 for assistance.
  • 178—Outdoor temperature sensor error. Call Golden Seal Service Experts at 630-246-2698 for assistance.
  • 181/182—Get a new air filter. Clear the monitor by tapping “dismiss” after adding a new filter.
  • 183—Rinse humidifier tank and install a new water filter. Clear the thermostat by touching “dismiss” after doing these procedures.
  • 184—Install a new humidifier pad. Clear the display by hitting “dismiss” after getting a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the display by touching “dismiss” after adding a new filter.
  • 186—Clean ventilator core. Clear the display by touching “dismiss” after doing this task.
  • 187—Wash or replace ventilator filter. Clear the monitor by hitting “dismiss” after getting a new filter.
  • 188/189—Install a new UV bulb. Reach Golden Seal Service Experts at 630-246-2698 for support.
  • 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 exterior temperature. Download the Lyric app to do 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 select new Wi-Fi network.
  • 508—Wi-Fi not configured. Use the Lyric app and follow the steps to connect your thermostat.

For more specifics, check this thermostat’s user manual.

Our Experts are Available to Provide Assistance

If you’re still experiencing problems after trying the troubleshooting process, our pros are here to support you. Call us at 630-246-2698 and we’ll be out quickly to determine the issue.

If you rely on a dated thermostat, now is a great time to think over a replacement. 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 bills year-round.

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