How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat producers, and we proudly install them on a usual basis in East Syracuse. They’re long-lasting and trustworthy. Also, Honeywell is constantly enhancing its technology, bringing more features for your house.

However, every thermostat can experience problems every now and then. As a result, we’ve prepared this helpful guidebook to run through troubleshooting. While Honeywell thermostat problems are rare, they happen. 

While you can usually repair the majority of thermostat issues on your own, they sometimes require Expert help. Our HVAC pros are available to support you when you need us. We’re only a call away at 315-313-6531.

Let’s get started with the process by determining what kind of thermostat your home has.

What Kind of Thermostat Do I Have?

There are three models of thermostats:

  • Manual—This is the typical dial-shaped thermostat. You won’t have error codes with this kind, but it’s also the least efficient for lowering utility expenses.
  • Programmable—This thermostat features a digital screen and arrows you touch to determine your desired temperature. You can also set daily programs to lower the temperature when you’re at work and set it higher when you return.
  • Smart—You won’t have to set any programs on this thermostat, as it adjusts to your schedule. It automatically adjusts the temperature when you or family members are out and about to help you save on heating and cooling costs. You can also adjust the temperature anywhere on your phone or other Wi-Fi-enabled device. 

As you’re aware many technologically advanced solutions, there are several problems that can happen. The majority of of these issues don’t need pro help and are uncomplicated enough to solve alone.

Common Honeywell Thermostat Troubles

Each thermostat has a special group of codes assigned to the troubles that happen.

Think how uncomplicated 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 listing the most common Honeywell thermostat problems. These are applicable to the following programmable thermostats:

Display is Blank

If the monitor is blank on your programmable thermostat, you may need to put in new batteries. If that doesn’t fix the problem or you rely on a smart thermostat, there may be a wiring malfunction.

Next, you should ensure the power is on for your furnace or air handler. Confirm the switch near the indoor unit is in the “on” position.

Also, you should make sure all furnace cabinet or air handler doors/panels are sturdily fastened.

An unsecured panel may trip the safety switch, which disconnects power to the unit.

While it’s less common, a clear monitor could mean you will need to install a new thermostat.

Comfort Equipment Won’t Work

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

During warm weather, make sure you put the thermostat below the room temperature. When it’s cold, confirm it’s higher. This sounds absurd, but we’ve seen it take place a lot of times.

Make sure the power switch by 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. A loose panel can activate the safety switch, stopping current to the equipment.

System still won’t turn on? Verify circuit breakers haven’t turned off and that your HVAC unit isn’t showing error codes.

“Cool On” or “Heat On” is Flickering

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

Then, check it’s calling for the appropriate unit to turn on. This is often shown by “cool on,” “heat on” or an icon.

If this phrase or the picture is pulsing, your thermostat is in a five-minute delay status. This setting stops your equipment from bad short cycling. This can take place if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump needs service. Call Falso Service Experts at 315-313-6531 for assistance.
  • 168—Wi-Fi radio error. Reach Lyric technical support at 800-633-3991. 170—Internal memory error. Reach Lyric technical support at 800-633-3991.
  • 171—Set date and time. Finalize these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Contact Lyric technical support at 800-633-3991.
  • 175—AC power resumed. No action necessary.
  • 181/182—Install a new air filter. Clear the display by hitting “dismiss” after putting in a fresh filter.
  • 184—Put in a new humidifier pad. Clear the monitor by hitting “dismiss” after adding a clean 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 thermostat by hitting “dismiss” after putting in a new filter.
  • 188/189—Get a new UV bulb. Contact Falso Service Experts at 315-313-6531 for help.
  • 210—Register online for exterior temperature. Download the Lyric app to do this step and ensure correct thermostat operation.
  • 388—Register online for remote access and exterior 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 pick new Wi-Fi network.
  • 508—Wi-Fi not configured. Use the Lyric app and follow the procedure to configure your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump must be serviced service. Call Falso Service Experts at 315-313-6531 for help.
  • 168—Wi-Fi radio error. Reach Falso Service Experts at 315-313-6531 for help.
  • 170—Internal memory error. Call Falso Service Experts at 315-313-6531 for help.
  • 171—Set date and time. Complete these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Call Falso Service Experts at 315-313-6531 for assistance.
  • 175—AC power resumed. No action necessary.
  • 177—Indoor temperature sensor error. Reach Falso Service Experts at 315-313-6531 for assistance.
  • 178—Outdoor temperature sensor error. Contact Falso Service Experts at 315-313-6531 for assistance.
  • 181/182—Install a new air filter. Clear the thermostat by tapping “dismiss” after installing a new filter.
  • 183—Rinse humidifier tank and install a new water filter. Clear the thermostat by hitting “dismiss” after finishing these procedures.
  • 184—Get a new humidifier pad. Clear the thermostat by touching “dismiss” after installing pad filter.
  • 185—Replace dehumidifier filter. Clear the thermostat by touching “dismiss” after adding a fresh filter.
  • 186—Wash ventilator core. Clear the screen by touching “dismiss” after finishing this task.
  • 187—Rinse or install a new ventilator filter. Clear the monitor by hitting “dismiss” after installing a new filter.
  • 188/189—Get a new UV bulb. Reach Falso Service Experts at 315-313-6531 for help.
  • 210—Register online for outside temperature. Download the Lyric app to finish this step and ensure correct thermostat operation.
  • 388—Register online for remote access and outside temperature. Use 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 connected. Use the Lyric app and follow the process to connect your thermostat.

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

Our Experts are Ready to Help

If you’re still having troubles after trying the troubleshooting steps, our professionals are ready to help. Give us a call at 315-313-6531 and we’ll come to your house rapidly to determine the problem.

If you rely on an aging thermostat, today is a great time to consider a replacement. Thermostat technology has advanced in recent years Ask us for more information on how smart thermostats can make your house comfier while helping save on energy bills year-round.

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