How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat producers, and we proudly install them on a usual basis in Albany. They’re sturdy and trustworthy. In addition, Honeywell is frequently updating its technology, bringing more features for your family.

Nevertheless, each thermostat can run into issues at one time or another. That’s why we’ve put together this helpful guidebook to run through troubleshooting.

While you can usually repair many thermostat troubles alone, they often need Expert help. Our HVAC Experts are here to support you when you need us. We’re merely a call away at 518-205-3324.

Let’s start the process by finding out what type of thermostat your residence 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 experience error codes with this one, but it’s also the least efficient for saving on heating and cooling bills.
  • Programmable—This thermostat has a digital screen and arrows you press to choose your desired temperature. You can also set daily programs to decrease the temperature when you’re at work and set it higher when you come home.
  • Smart—You won’t have to schedule any programs on this thermostat, as it adjusts to your schedule. It automatically changes the temperature when you or other household members are out and about to help you save on utility bills. You can also raise or lower the temperature anywhere via your phone or other Wi-Fi-enabled device. 

As you know many technologically advanced products, there are several malfunctions that might occur. Most of these troubles don’t call for Expert help and are uncomplicated enough to fix by yourself.

Common Honeywell Thermostat Problems

Each thermostat has an exclusive group of codes that correspond to the glitches that occur.

Think how uncomplicated it can be to fix a computer by restarting it. In most situations, troubleshooting a thermostat can be just as simple.

Here is a listing the most reported Honeywell thermostat issues. These include the following programmable thermostats:

Display is Blank

If the display is empty on your programmable thermostat, you might need to install new batteries. If that doesn’t fix the trouble or you use a smart thermostat, there may be a wiring issue.

Next, you should check the power is on for your furnace or air handler. Verify the switch close to the indoor unit is in the “on” position.

Additionally, you should confirm all furnace cabinet or air handler doors/panels are securely secured.

A loose panel may activate the safety switch, which stops power to the equipment.

Less frequently, a clear display can signify you should install a new thermostat.

HVAC Unit Won’t Work

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

In the summer, verify you schedule the thermostat beneath the room temperature. In the winter, verify it’s higher. This sounds goofy, but we’ve seen it take place lots of times.

Ensure the power switch near your indoor unit is in the “on” position. You should also comfirm the cabinet doors or panels are tight on your furnace cabinet or air handler. A loose panel can trigger the safety switch, stopping current to the equipment.

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

“Cool On” or “Heat On” is Flickering

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

Then, check it’s telling the appropriate unit to start. This is usually shown by “cool on,” “heat on” or an illustration.

If this set of words or the illustration is flashing, your thermostat is in a five-minute delay status. This mode stops your system from damaging short cycling. This may take place if you lose power.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump must be serviced. Call D.A. Bennett Service Experts at 518-205-3324 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. Finalize 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—Replace air filter. Clear the monitor by hitting “dismiss” after putting in a fresh filter.
  • 184—Install a new humidifier pad. Clear the monitor by hitting “dismiss” after installing a clean pad filter.
  • 185—Install a new dehumidifier filter. Clear the display by touching “dismiss” after adding a fresh filter.
  • 187—Clean or install a new ventilator filter. Clear the thermostat by tapping “dismiss” after putting in a new filter.
  • 188/189—Get a new UV bulb. Ring D.A. Bennett Service Experts at 518-205-3324 for support.
  • 210—Register online for outdoor temperature. Get the Lyric app to complete this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and exterior temperature. Use the Lyric app to finish this step and ensure correct thermostat operation.
  • 399—No Internet. Check 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 process to link your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump needs service. Contact D.A. Bennett Service Experts at 518-205-3324 for support.
  • 168—Wi-Fi radio error. Call D.A. Bennett Service Experts at 518-205-3324 for support.
  • 170—Internal memory error. Contact D.A. Bennett Service Experts at 518-205-3324 for assistance.
  • 171—Set date and time. Finish these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Call D.A. Bennett Service Experts at 518-205-3324 for support.
  • 175—AC power resumed. No action necessary.
  • 177—Indoor temperature sensor error. Call D.A. Bennett Service Experts at 518-205-3324 for help.
  • 178—Outdoor temperature sensor error. Call D.A. Bennett Service Experts at 518-205-3324 for help.
  • 181/182—Install a new air filter. Clear the screen by touching “dismiss” after installing a clean filter.
  • 183—Wash humidifier tank and replace water filter. Clear the monitor by touching “dismiss” after finishing these tasks.
  • 184—Replace humidifier pad. Clear the monitor by hitting “dismiss” after adding a new pad filter.
  • 185—Get a new dehumidifier filter. Clear the screen by hitting “dismiss” after putting in a clean filter.
  • 186—Wash ventilator core. Clear the monitor by touching “dismiss” after doing this task.
  • 187—Wash or get a new ventilator filter. Clear the monitor by tapping “dismiss” after getting a new filter.
  • 188/189—Replace UV bulb. Get in touch with D.A. Bennett Service Experts at 518-205-3324 for assistance.
  • 210—Register online for outside temperature. Use the Lyric app to do this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and outdoor temperature. Get the Lyric app to finish this step and ensure correct thermostat operation.
  • 399—No Internet. Check 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. Use the Lyric app and follow the steps to connect your thermostat.

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

Our Experts are Available to Provide Support

If you’re still having issues after going through the troubleshooting list, our pros are ready to help. Give us a call at 518-205-3324 and we’ll come to your house as fast as we can to figure out the issue.

If you use an aging thermostat, now is a fantastic time to consider a new thermostat. Thermostat technology has come a long way in recent years Ask us for more details on how smart thermostats can make your home more convenient while helping save on energy expenses throughout the year.

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