How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat producers, and we proudly install them on a usual basis in Daytona Beach. They’re long-lasting and reliable. In addition, Honeywell is regularly enhancing its technology, bringing more features for your family.

Nevertheless, all thermostats can experience troubles every so often. As a result, we’ve put together this helpful manual to walk you through troubleshooting.

While you can often repair many thermostat issues alone, they sometimes call for Expert support. Our heating and cooling pros are here to help when you need us. We’re only a call away at 386-310-2061.

Let’s start the process by determining what kind of thermostat your residence has.

What Type of Thermostat Do I Have?

There are three types of thermostats:

  • Manual—This is the classic dial-shaped thermostat. You won’t experience error codes with this one, but it’s also the least efficient for lowering utility bills.
  • Programmable—This thermostat features a digital screen and arrows you use to determine your desired temperature. You can also choose daily programs to decrease the temperature when you’re at work and increase it when you get back.
  • Smart—You won’t have to set any programs on this thermostat, as it learns your schedule. It intuitively raises and lowers the temperature when you or family members are away to help you save on utility expenses. You can also change the temperature anywhere via your phone or other Wi-Fi-enabled device. 

As you know most technologically advanced things, there are common malfunctions that might occur. The majority of of these troubles don’t require professional assistance and are simple to repair alone.

Common Honeywell Thermostat Problems

Every thermostat has an exclusive group of codes that correspond to the issues that occur.

Think how easy it can be to restore a computer by restarting it. In most situations, diagnosing a thermostat can be just as easy.

Here is a guide to the most encountered Honeywell thermostat problems. These include the following programmable thermostats:

Display is Blank

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

Next, you should make sure the power is on for your furnace or air handler. Verify the switch by the indoor equipment is switched “up”.

Additionally, you should make sure all furnace cabinet or air handler doors/panels are sturdily in place.

A loose panel may trigger the safety switch, which stops power to the system.

Infrequently, an empty screen could mean you should buy a new thermostat.

HVAC Unit Won’t Work

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

When it’s hot, confirm you put the thermostat lower than the current temperature. When it’s cool, confirm it’s higher. This sounds goofy, but we’ve seen it take place a lot 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. A loose panel can trigger the safety switch, diverting power to the equipment.

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

“Cool On” or “Heat On” is Flickering

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

Then, make sure it’s telling the correct system to run. This is usually shown by “cool on,” “heat on” or an illustration.

If this phrase or the illustration is pulsing, your thermostat is in a five-minute delay status. This feature keeps your equipment from bad short cycling. This may happen if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump must be serviced. Call All American Air Service Experts at 386-310-2061 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. Complete these settings so scheduling can occur.
  • 173—Thermostat temperature sensor error. Call Lyric technical support at 800-633-3991.
  • 175—AC power resumed. No action necessary.
  • 181/182—Replace air filter. Clear the display by touching “dismiss” after installing a fresh filter.
  • 184—Put in a new humidifier pad. Clear the monitor by hitting “dismiss” after installing a new pad filter.
  • 185—Replace dehumidifier filter. Clear the screen by tapping “dismiss” after installing a fresh filter.
  • 187—Wash or install a new ventilator filter. Clear the screen by hitting “dismiss” after putting in a clean filter.
  • 188/189—Install a new UV bulb. Contact All American Air Service Experts at 386-310-2061 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 outdoor temperature. Use the Lyric app to complete this step and ensure accurate 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. Get the Lyric app and follow the process to link your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump requires service. Contact All American Air Service Experts at 386-310-2061 for assistance.
  • 168—Wi-Fi radio error. Call All American Air Service Experts at 386-310-2061 for help.
  • 170—Internal memory error. Reach All American Air Service Experts at 386-310-2061 for assistance.
  • 171—Set date and time. Complete these settings so scheduling can work.
  • 173—Thermostat temperature sensor error. Reach All American Air Service Experts at 386-310-2061 for help.
  • 175—AC power restored. No action necessary.
  • 177—Indoor temperature sensor error. Contact All American Air Service Experts at 386-310-2061 for assistance.
  • 178—Outdoor temperature sensor error. Call All American Air Service Experts at 386-310-2061 for support.
  • 181/182—Get a new air filter. Clear the thermostat by touching “dismiss” after putting in a new filter.
  • 183—Clean humidifier tank and install a new water filter. Clear the screen by hitting “dismiss” after finishing these steps.
  • 184—Get a new humidifier pad. Clear the monitor by hitting “dismiss” after adding a new pad filter.
  • 185—Replace dehumidifier filter. Clear the screen by hitting “dismiss” after adding a new filter.
  • 186—Wash ventilator core. Clear the screen by touching “dismiss” after completing this task.
  • 187—Rinse or get a new ventilator filter. Clear the display by hitting “dismiss” after getting a new filter.
  • 188/189—Add a new UV bulb. Get in touch with All American Air Service Experts at 386-310-2061 for assistance.
  • 210—Register online for exterior temperature. Use the Lyric app to finish this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and outside temperature. Get 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 pick new Wi-Fi network.
  • 508—Wi-Fi not connected. Download the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Ready to Provide Assistance

If you’re still running into problems after working through the troubleshooting steps, our pros are here to assist you. Give us a call at 386-310-2061 and we’ll be out as fast as we can to figure out the issue.

If you have an older thermostat, right now is a great time to consider a new thermostat. Thermostat technology has come a long way over the last few years. Ask us for more information on how smart thermostats can make your home better while helping save on energy expenses all year.

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