How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat brands, and we proudly install them on a regular basis in Edmonton. They’re durable and trustworthy. In addition, Honeywell is regularly enhancing its technology, bringing more features for your home.

Nevertheless, every thermostat can run into errors occasionally. Due to this, we’ve compiled this helpful guidebook to go over troubleshooting.

While you can usually fix most thermostat problems by yourself, they often require Expert help. Our heating and cooling professionals are available to support you when you need us. We’re merely a call away at 780-800-7092.

Let’s get started with the process by determining what type 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 have error codes with this one, but it’s also the least efficient for lowering energy bills.
  • Programmable—This thermostat features a digital screen and arrows you use to choose your desired temperature. You can also use daily programs to lower the temperature when you’re gone and raise it when you get back.
  • Smart—You won’t have to set any programs on this thermostat, as it learns your routine. It intuitively changes the temperature when you or other household members are out and about to help you save on energy bills. You can also raise or lower the temperature anywhere using your phone or other Wi-Fi-enabled device. 

As you know many technologically advanced solutions, there are several glitches that can happen. Most of these problems don’t call for pro help and are easy to repair on your own.

Common Honeywell Thermostat Issues

All thermostats have a special set of codes matching the glitches that occur.

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

Here is a listing the most reported Honeywell thermostat errors. These involve the following programmable thermostats:

Display is Blank

If the display is blank on your programmable thermostat, you could need to install new batteries. If that doesn’t take care of the malfunction or you have a smart thermostat, there might be a wiring issue.

Next, you should check the power is enabled for your furnace or air handler. Confirm the switch close to the indoor equipment is switched “up”.

Additionally, you should make certain all furnace cabinet or air handler doors/panels are tightly secured.

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

Less frequently, an empty display might signify you will need to get a new thermostat.

HVAC Unit Won’t Work

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

In the summer, confirm you set the thermostat lower than the ambient temperature. When it’s cold, verify it’s higher. This sounds silly, but we’ve seen it occur lots of times.

Make sure the power switch close to your indoor equipment is in the “on” position. You should also make sure the cabinet doors or panels are closed on your furnace cabinet or air handler. An open panel can activate the safety switch, diverting electricity to the unit.

Unit still won’t turn on? Verify circuit breakers haven’t turned off and that your HVAC equipment isn’t displaying error codes.

“Cool On” or “Heat On” is Flashing

To start, confirm your thermostat is set to “cool” or “heat.”

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

If these words or the illustration is blinking, your thermostat is in a five-minute delay mode. This mode stops your system 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 requires service. Call McKinley Heating Service Experts at 780-800-7092 for assistance.
  • 168—Wi-Fi radio error. Call Lyric technical support at 800-633-3991. 170—Internal memory error. Contact Lyric technical support at 800-633-3991.
  • 171—Set date and time. Complete these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Reach Lyric technical support at 800-633-3991.
  • 175—AC power restored. No action required.
  • 181/182—Replace air filter. Clear the thermostat by touching “dismiss” after putting in a clean filter.
  • 184—Put in a new humidifier pad. Clear the screen by hitting “dismiss” after adding a fresh pad filter.
  • 185—Put in a new dehumidifier filter. Clear the thermostat by touching “dismiss” after adding a new filter.
  • 187—Wash or put in a new ventilator filter. Clear the monitor by hitting “dismiss” after adding a clean filter.
  • 188/189—Install a new UV bulb. Contact McKinley Heating Service Experts at 780-800-7092 for help.
  • 210—Register online for exterior temperature. Download the Lyric app to do this step and ensure proper 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 set up. Download 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 requires service. Call McKinley Heating Service Experts at 780-800-7092 for assistance.
  • 168—Wi-Fi radio error. Contact McKinley Heating Service Experts at 780-800-7092 for help.
  • 170—Internal memory error. Reach McKinley Heating Service Experts at 780-800-7092 for support.
  • 171—Set date and time. Finalize these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Contact McKinley Heating Service Experts at 780-800-7092 for assistance.
  • 175—AC power resumed. No action needed.
  • 177—Indoor temperature sensor error. Contact McKinley Heating Service Experts at 780-800-7092 for support.
  • 178—Outdoor temperature sensor error. Reach McKinley Heating Service Experts at 780-800-7092 for help.
  • 181/182—Install a new air filter. Clear the monitor by hitting “dismiss” after putting in a clean filter.
  • 183—Clean humidifier tank and add a new water filter. Clear the display by tapping “dismiss” after completing these procedures.
  • 184—Get a new humidifier pad. Clear the monitor by touching “dismiss” after adding a new pad filter.
  • 185—Replace dehumidifier filter. Clear the monitor by tapping “dismiss” after installing a new filter.
  • 186—Wash ventilator core. Clear the display by hitting “dismiss” after completing this task.
  • 187—Rinse or replace ventilator filter. Clear the monitor by hitting “dismiss” after buying a new filter.
  • 188/189—Add a new UV bulb. Contact McKinley Heating Service Experts at 780-800-7092 for help.
  • 210—Register online for outdoor temperature. Get the Lyric app to complete this step and ensure proper thermostat operation.
  • 388—Register online for remote access and outdoor 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 configured. Get the Lyric app and follow the process to connect your thermostat.

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

Our Experts are Here to Help

If you’re still experiencing problems after working through the troubleshooting process, our professionals are available to assist you. Reach us at 780-800-7092 and we’ll arrive quickly to diagnose the malfunction.

If you rely on an aging thermostat, today is a great time to think about a new thermostat. Thermostat technology has gotten better in recent years Ask us for more info on how smart thermostats can make your home more comfortable while helping save on heating and cooling bills year-round.

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