How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat brands, and we proudly install them on a usual basis in Knoxville. They’re long-lasting and reliable. Also, Honeywell is regularly enhancing its technology, offering more features for your family.

Nevertheless, every thermostat can run into issues at one time or another. As a result, we’ve prepared this valuable guide to run through troubleshooting.

While you can usually fix the majority of thermostat problems by yourself, they often need Expert assistance. Our HVAC pros are ready to support you when you need us. We’re only a call away at 865-229-6176.

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

What Kind of Thermostat Do I Have?

There are three kinds 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 reducing energy expenses.
  • Programmable—This thermostat has a digital screen and arrows you use to determine your desired temperature. You can also set daily programs to reduce 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, since it picks up on your routine. It intuitively raises and lowers the temperature when you or other household members are out and about to help you save on energy costs. You can also raise or lower the temperature anywhere via your phone or other Wi-Fi-enabled device. 

As you know many technologically advanced solutions, there are several problems that can occur. Many of these problems don’t require Expert assistance and are easy to repair by yourself.

Common Honeywell Thermostat Issues

All thermostats have a special set of codes assigned to the issues that take place.

Think how uncomplicated it can be to restore a computer by restarting it. For the most part, diagnosing a thermostat can be just as uncomplicated.

Here is a listing the most common Honeywell thermostat issues. These are applicable to the following programmable thermostats:

Display is Blank

If the display is clear on your programmable thermostat, you might need to replace the batteries. If that doesn’t take care of the trouble or you rely on a smart thermostat, there might be a wiring issue.

Next, you should ensure the power is enabled for your furnace or air handler. Make sure the switch near the indoor unit is switched “on”.

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

A panel that isn’t tight may trip the safety switch, which cuts off power to the unit.

While it’s less common, a clear screen could mean you need to replace your thermostat.

Comfort System Won’t Turn On

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

During warm weather, confirm you set the thermostat lower than the room temperature. When it’s cool, make sure it’s higher. This sounds absurd, but we’ve seen it occur many times.

Confirm the power switch by your indoor system is in the “on” position. You should also comfirm the cabinet doors or panels are secure on your furnace cabinet or air handler. An unsecured panel can trip the safety switch, stopping current to the system.

Heating or cooling still won’t turn on? Verify circuit breakers haven’t flipped and that your HVAC equipment isn’t displaying error codes.

“Cool On” or “Heat On” is Blinking

To start, check your thermostat is on “cool” or “heat.”

Then, check it’s signaling the right system to run. This is typically demonstrated 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 state. This mode 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 needs service. Call R & M Climate Control Service Experts at 865-229-6176 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. Finish these settings so scheduling can occur.
  • 173—Thermostat temperature sensor error. Call Lyric technical support at 800-633-3991.
  • 175—AC power restored. No action needed.
  • 181/182—Replace air filter. Clear the screen by hitting “dismiss” after putting in a clean filter.
  • 184—Replace humidifier pad. Clear the thermostat by touching “dismiss” after installing a clean pad filter.
  • 185—Replace dehumidifier filter. Clear the screen by touching “dismiss” after putting in a new filter.
  • 187—Clean or replace ventilator filter. Clear the display by hitting “dismiss” after adding a new filter.
  • 188/189—Replace UV bulb. Ring R & M Climate Control Service Experts at 865-229-6176 for support.
  • 210—Register online for outside temperature. Use the Lyric app to finish this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and outdoor temperature. Use the Lyric app to do this step and ensure proper 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 connect your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump needs service. Reach R & M Climate Control Service Experts at 865-229-6176 for support.
  • 168—Wi-Fi radio error. Contact R & M Climate Control Service Experts at 865-229-6176 for assistance.
  • 170—Internal memory error. Reach R & M Climate Control Service Experts at 865-229-6176 for help.
  • 171—Set date and time. Finalize these settings so scheduling can work.
  • 173—Thermostat temperature sensor error. Call R & M Climate Control Service Experts at 865-229-6176 for support.
  • 175—AC power restored. No action required.
  • 177—Indoor temperature sensor error. Call R & M Climate Control Service Experts at 865-229-6176 for support.
  • 178—Outdoor temperature sensor error. Contact R & M Climate Control Service Experts at 865-229-6176 for help.
  • 181/182—Get a new air filter. Clear the thermostat by tapping “dismiss” after installing a clean filter.
  • 183—Rinse humidifier tank and replace water filter. Clear the monitor by tapping “dismiss” after finishing these procedures.
  • 184—Replace humidifier pad. Clear the screen by hitting “dismiss” after adding a new pad filter.
  • 185—Replace dehumidifier filter. Clear the screen by touching “dismiss” after adding a new filter.
  • 186—Wash ventilator core. Clear the display by hitting “dismiss” after completing this task.
  • 187—Rinse or install a new ventilator filter. Clear the screen by touching “dismiss” after buying a new filter.
  • 188/189—Add a new UV bulb. Get in touch with R & M Climate Control Service Experts at 865-229-6176 for assistance.
  • 210—Register online for outdoor temperature. Download 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 complete 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 select new Wi-Fi network.
  • 508—Wi-Fi not configured. Use the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Here to Provide Assistance

If you’re still running into troubles after trying the troubleshooting steps, our pros are ready to help. Reach us at 865-229-6176 and we’ll come to your house quickly to diagnose the issue.

If you rely on an aging thermostat, right now is a fantastic time to think about a new thermostat. Thermostat technology has come a long way over the last few years. Ask us for more info on how smart thermostats can make your residence more comfortable while helping save on heating and cooling expenses all year.

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