How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the best thermostat brands, and we proudly install them on a regular basis in Indianapolis. They’re long-lasting and dependable. Also, Honeywell is frequently advancing its technology, bringing more features for your home.

Still, all thermostats can run into issues once in awhile. As a result, we’ve put together this valuable manual to go over troubleshooting.

While you can typically solve the majority of thermostat issues on your own, they often require Expert support. Our home comfort Experts are ready to support you when you need us. We’re only a call away at 317-527-0271.

Let’s begin the process by determining what model of thermostat your house has.

What Model of Thermostat Do I Have?

There are three kinds of thermostats:

  • Manual—This is the older dial-shaped thermostat. You won’t experience error codes with this type, but it’s also the least efficient for reducing heating and cooling bills.
  • Programmable—This thermostat includes a digital screen and arrows you touch to choose your desired temperature. You can also use daily programs to reduce the temperature when you’re gone and increase it when you get back.
  • Smart—You won’t have to set any programs on this thermostat, because it adjusts to your day. It instinctively raises and lowers the temperature when you or loved ones 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 is the case with the majority of technologically advanced products, there are regular problems that might take place. Most of these issues don’t require Expert help and are simple to repair by yourself.

Common Honeywell Thermostat Problems

Each thermostat has a special kind of codes matching the glitches that happen.

Think how uncomplicated it can be to fix a computer by restarting it. Many times, correcting a thermostat can be just as uncomplicated.

Here is a guide to the most reported Honeywell thermostat errors. These include 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 take care of the problem or you use a smart thermostat, there may be a wiring malfunction.

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

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

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

While it’s less common, an empty monitor may signify you will need to install a new thermostat.

Heating and Cooling Equipment Won’t Start

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

During warm weather, confirm you set the thermostat beneath the room temperature. When it’s cold, verify it’s higher. This sounds absurd, but we’ve seen it occur a lot of times.

Confirm the power switch close to your indoor system 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, cutting off power to the equipment.

Heating or cooling still won’t run? Confirm circuit breakers haven’t turned off and that your HVAC system isn’t showing error codes.

“Cool On” or “Heat On” is Flickering

First, confirm your thermostat is on “cool” or “heat.”

Then, check it’s calling for the appropriate system to start. This is typically shown by “cool on,” “heat on” or a picture.

If this set of words or the illustration is flashing, your thermostat is in a five-minute delay mode. This setting keeps your unit from bad short cycling. This can happen if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump must be serviced. Call Broad Ripple Service Experts at 317-527-0271 for help.
  • 168—Wi-Fi radio error. Reach Lyric technical support at 800-633-3991. 170—Internal memory error. Call Lyric technical support at 800-633-3991.
  • 171—Set date and time. Complete these settings so scheduling can occur.
  • 173—Thermostat temperature sensor error. Contact Lyric technical support at 800-633-3991.
  • 175—AC power restarted. No action necessary.
  • 181/182—Replace air filter. Clear the thermostat by touching “dismiss” after installing a new filter.
  • 184—Install a new humidifier pad. Clear the screen by touching “dismiss” after putting in a fresh pad filter.
  • 185—Install a new dehumidifier filter. Clear the thermostat by tapping “dismiss” after installing a fresh filter.
  • 187—Wash or put in a new ventilator filter. Clear the monitor by hitting “dismiss” after adding a new filter.
  • 188/189—Replace UV bulb. Contact Broad Ripple Service Experts at 317-527-0271 for assistance.
  • 210—Register online for exterior temperature. Download the Lyric app to complete 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 proper thermostat operation.
  • 399—No Internet. Confirm 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. Download the Lyric app and follow the procedure to connect your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump needs service. Reach Broad Ripple Service Experts at 317-527-0271 for help.
  • 168—Wi-Fi radio error. Reach Broad Ripple Service Experts at 317-527-0271 for help.
  • 170—Internal memory error. Reach Broad Ripple Service Experts at 317-527-0271 for help.
  • 171—Set date and time. Finalize these settings so scheduling can work.
  • 173—Thermostat temperature sensor error. Reach Broad Ripple Service Experts at 317-527-0271 for support.
  • 175—AC power restored. No action needed.
  • 177—Indoor temperature sensor error. Call Broad Ripple Service Experts at 317-527-0271 for help.
  • 178—Outdoor temperature sensor error. Contact Broad Ripple Service Experts at 317-527-0271 for support.
  • 181/182—Get a new air filter. Clear the screen by touching “dismiss” after putting in a clean filter.
  • 183—Wash humidifier tank and install a new water filter. Clear the display by tapping “dismiss” after doing these tasks.
  • 184—Install a new humidifier pad. Clear the screen by tapping “dismiss” after installing pad filter.
  • 185—Get a new dehumidifier filter. Clear the monitor by touching “dismiss” after putting in a clean filter.
  • 186—Clean ventilator core. Clear the thermostat by hitting “dismiss” after doing this task.
  • 187—Wash or replace ventilator filter. Clear the screen by tapping “dismiss” after buying a new filter.
  • 188/189—Get a new UV bulb. Get in touch with Broad Ripple Service Experts at 317-527-0271 for help.
  • 210—Register online for outdoor temperature. Use the Lyric app to finish this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and outside temperature. Use 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 pick new Wi-Fi network.
  • 508—Wi-Fi not configured. Use the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Ready to Provide Assistance

If you’re still experiencing problems after trying the troubleshooting process, our pros are available to support you. Call us at 317-527-0271 and we’ll be out as fast as we can to diagnose the problem.

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

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