How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the best thermostat manufacturers, and we proudly install them on a usual basis in Elkhart. They’re sturdy and trustworthy. Also, Honeywell is frequently improving its technology, offering more features for your house.

Still, every thermostat can experience errors every now and then. That’s why we’ve put together this informative manual to go over troubleshooting. While Honeywell thermostat problems are rare, they do pop up. 

While you can usually repair many thermostat issues by yourself, they sometimes need Expert help. Our heating and cooling pros are here to help when you need us. We’re merely a call away at 574-218-6404.

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

What Model of Thermostat Do I Have?

There are three kinds of thermostats:

  • Manual—This is the classic dial-shaped thermostat. You won’t have error codes with this kind, but it’s also the least efficient for reducing heating and cooling bills.
  • Programmable—This thermostat features a digital screen and arrows you use to choose your desired temperature. You can also set daily programs to reduce the temperature when you’re at work and increase it when you return.
  • Smart—You won’t have to set any programs on this thermostat, since it adjusts to your schedule. It automatically raises and lowers the temperature when you or family members are away to help you save on heating and cooling costs. You can also adjust the temperature anywhere via your phone or other Wi-Fi-enabled device. 

As you’re aware many technologically advanced things, there are regular problems that can happen. The majority of of these troubles don’t require pro help and are easy to solve on your own.

Common Honeywell Thermostat Issues

Every thermostat has a special kind of codes assigned to the problems that take place.

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

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

Display is Blank

If the monitor is clear on your programmable thermostat, you may need to get 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 make sure the power is flowing for your furnace or air handler. Verify the switch by the indoor system is switched “up”.

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

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

Infrequently, an empty monitor could signify you need to install a new thermostat.

HVAC Unit Won’t Turn On

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

During warm weather, confirm you set the thermostat lower than the ambient temperature. When it’s cold, confirm it’s higher. This sounds absurd, but we’ve seen it take place a lot of times.

Ensure the power switch by your indoor unit 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 activate the safety switch, diverting power to the unit.

Equipment still won’t run? Verify circuit breakers haven’t tripped and that your HVAC equipment isn’t showing error codes.

“Cool On” or “Heat On” is Flashing

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

Then, verify it’s signaling the correct equipment to turn on. This is often indicated by “cool on,” “heat on” or an illustration.

If these words or the picture is flashing, your thermostat is in a five-minute delay mode. This feature stops your unit from bad 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 BW/Cook Service Experts at 574-218-6404 for support.
  • 168—Wi-Fi radio error. Contact Lyric technical support at 800-633-3991. 170—Internal memory error. Reach Lyric technical support at 800-633-3991.
  • 171—Set date and time. Complete these settings so scheduling can take place.
  • 173—Thermostat temperature sensor error. Call Lyric technical support at 800-633-3991.
  • 175—AC power restarted. No action required.
  • 181/182—Put in a new air filter. Clear the display by touching “dismiss” after putting in a fresh filter.
  • 184—Replace humidifier pad. Clear the monitor by hitting “dismiss” after adding a clean pad filter.
  • 185—Replace dehumidifier filter. Clear the display by hitting “dismiss” after installing a fresh filter.
  • 187—Rinse or install a new ventilator filter. Clear the monitor by tapping “dismiss” after installing a new filter.
  • 188/189—Install a new UV bulb. Ring BW/Cook Service Experts at 574-218-6404 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 outside temperature. Get the Lyric app to complete 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 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 requires service. Reach BW/Cook Service Experts at 574-218-6404 for assistance.
  • 168—Wi-Fi radio error. Contact BW/Cook Service Experts at 574-218-6404 for assistance.
  • 170—Internal memory error. Contact BW/Cook Service Experts at 574-218-6404 for help.
  • 171—Set date and time. Finalize these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Reach BW/Cook Service Experts at 574-218-6404 for help.
  • 175—AC power reconnected. No action needed.
  • 177—Indoor temperature sensor error. Call BW/Cook Service Experts at 574-218-6404 for support.
  • 178—Outdoor temperature sensor error. Call BW/Cook Service Experts at 574-218-6404 for help.
  • 181/182—Replace air filter. Clear the display by hitting “dismiss” after putting in a new filter.
  • 183—Wash humidifier tank and install a new water filter. Clear the screen by touching “dismiss” after completing these steps.
  • 184—Get a new humidifier pad. Clear the screen by hitting “dismiss” after getting a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the monitor by hitting “dismiss” after adding a new filter.
  • 186—Rinse ventilator core. Clear the display by touching “dismiss” after doing this task.
  • 187—Clean or get a new ventilator filter. Clear the display by hitting “dismiss” after installing a new filter.
  • 188/189—Replace UV bulb. Reach BW/Cook Service Experts at 574-218-6404 for help.
  • 210—Register online for exterior 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 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 select new Wi-Fi network.
  • 508—Wi-Fi not configured. Get the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Available to Help

If you’re still experiencing troubles after going through the troubleshooting steps, our professionals are ready to support you. Reach us at 574-218-6404 and we’ll arrive quickly to figure out the issue.

If you use an older thermostat, right now is a great time to think over a replacement. Thermostat technology has come a long way in recent years Ask us for more details on how smart thermostats can make your residence more convenient while helping save on heating and cooling expenses throughout the year.

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