How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat manufacturers, and we proudly install them on a usual basis in Saint Charles. They’re sturdy and dependable. Also, Honeywell is regularly improving its technology, bringing more features for your family.

Still, each thermostat can have errors every now and then. That’s why we’ve prepared this informative guidebook to go over troubleshooting.

While you can usually fix many thermostat problems on your own, they occasionally require Expert assistance. Our home comfort professionals 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 determining what type of thermostat your house 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 costs.
  • Programmable—This thermostat includes a digital screen and arrows you touch to determine your desired temperature. You can also set daily programs to decrease the temperature when you’re gone and set it higher when you get back.
  • Smart—You won’t have to make any programs on this thermostat, because it picks up on your routine. It instinctively raises and lowers the temperature when you or other household members are out and about to help you save on heating and cooling costs. You can also raise or lower the temperature anywhere via your phone or other Wi-Fi-enabled device. 

As you’re aware the majority of technologically advanced solutions, there are regular malfunctions that may occur. The majority of 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 problems that occur.

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

Here is a guide to the most encountered Honeywell thermostat errors. These are applicable to the following programmable thermostats:

Display is Blank

If the monitor is blank on your programmable thermostat, you could 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 ensure 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 system.

Less frequently, a clear display might indicate you will need to replace your thermostat.

Comfort System Won’t Turn On

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

When it’s hot, make sure you schedule the thermostat lower than the room temperature. When it’s cold, 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, diverting power to the system.

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

“Cool On” or “Heat On” is Flickering

To start, verify your thermostat is switched to “cool” or “heat.”

Then, verify it’s telling the right unit to turn on. This is typically indicated by “cool on,” “heat on” or a picture.

If this phrase or the icon is flashing, your thermostat is in a five-minute delay state. This setting protects your unit from bad short cycling. This may take place if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump requires service. Call Golden Seal Service Experts at 630-246-2698 for help.
  • 168—Wi-Fi radio error. Reach Lyric technical support at 800-633-3991. 170—Internal memory error. Contact 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. Reach Lyric technical support at 800-633-3991.
  • 175—AC power restored. No action needed.
  • 181/182—Install a new air filter. Clear the screen by hitting “dismiss” after installing a new filter.
  • 184—Install a new humidifier pad. Clear the display by touching “dismiss” after installing a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the display by tapping “dismiss” after adding a fresh filter.
  • 187—Rinse or put in a new ventilator filter. Clear the thermostat by hitting “dismiss” after adding a new filter.
  • 188/189—Install a new UV bulb. Ring Golden Seal Service Experts at 630-246-2698 for help.
  • 210—Register online for outside temperature. Get the Lyric app to complete this step and ensure proper thermostat operation.
  • 388—Register online for remote access and outside temperature. Get the Lyric app to do 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, look at 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 help.
  • 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 reconnected. No action required.
  • 177—Indoor temperature sensor error. Reach 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—Install a new air filter. Clear the monitor by tapping “dismiss” after adding a new filter.
  • 183—Wash humidifier tank and install a new water filter. Clear the thermostat by touching “dismiss” after finishing these steps.
  • 184—Install a new humidifier pad. Clear the screen by tapping “dismiss” after getting a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the display by touching “dismiss” after putting in a new filter.
  • 186—Clean ventilator core. Clear the screen by touching “dismiss” after doing this task.
  • 187—Wash or replace ventilator filter. Clear the monitor by tapping “dismiss” after buying a new filter.
  • 188/189—Install a new UV bulb. Reach Golden Seal Service Experts at 630-246-2698 for help.
  • 210—Register online for outside temperature. Use the Lyric app to do this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and outside temperature. Download the Lyric app to do 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 configured. Get the Lyric app and follow the steps to connect your thermostat.

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

Our Experts are Available to Provide Support

If you’re still running into problems after going through the troubleshooting process, our pros are here to assist you. Reach us at 630-246-2698 and we’ll be out quickly to figure out the issue.

If you use a dated thermostat, now is a great time to think over a replacement. Thermostat technology has advanced 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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