How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat brands, and we proudly install them on a frequent basis in Fort Worth. They’re durable and dependable. In addition, Honeywell is regularly updating its technology, offering more features for your residence.

Still, every thermostat can experience problems now and again. That’s why we’ve put together this useful handbook to run through troubleshooting. While Honeywell thermostat troubleshooting problems are rare, they do occur.

While you can often repair many thermostat issues on your own, they occasionally call for Expert support. Our home comfort Experts are here to help when you need us. We’re just a call away at 817-380-5647.

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

What Kind of Thermostat Do I Have?

There are three kinds of thermostats:

  • Manual—This is the typical dial-shaped thermostat. You won’t experience error codes with this kind, but it’s also the least efficient for reducing heating and cooling costs.
  • Programmable—This thermostat includes a digital screen and arrows you touch to choose your desired temperature. You can also set daily programs to decrease the temperature when you’re gone and increase it when you come home.
  • Smart—You won’t have to schedule any programs on this thermostat, since it adjusts to your routine. It automatically adjusts the temperature when you or family members are gone to help you save on energy costs. You can also adjust the temperature anywhere on your phone or other Wi-Fi-enabled device.

As you know many technologically advanced solutions, there are regular glitches that may occur. Most of these problems don’t call for Expert assistance and are simple to repair on your own.

Common Honeywell Thermostat Troubleshooting Errors

Every Honeywell thermostat has a special group of codes matching the malfunctions that occur.

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

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

Display is Blank

If the display is clear on your programmable thermostat, you may need to install new batteries. If that doesn’t solve the trouble or you have a smart thermostat, there may be a wiring problem.

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

In addition to that, you should make certain all furnace cabinet or air handler doors/panels are tightly fastened.

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

Less frequently, an empty display might indicate you should install a new thermostat.

Heating and Cooling Unit Won’t Start

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

When it’s hot, confirm you put the thermostat below the current temperature. When it’s cold, confirm it’s higher. This sounds absurd, but we’ve seen it take place lots of times.

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

Heating or cooling still won’t start? Verify circuit breakers haven’t turned off and that your HVAC unit isn’t showing error codes.

“Cool On” or “Heat On” is Blinking

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

Then, check it’s calling for the right equipment to run. This is typically demonstrated by “cool on,” “heat on” or an illustration.

If this phrase or the picture is pulsing, your thermostat is in a five-minute delay status. This mode stops your equipment from damaging short cycling. This may take place if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump requires service. Call Calverley Service Experts at 817-380-5647 for assistance.
  • 168—Wi-Fi radio error. Call Lyric technical support at 800-633-3991. 170—Internal memory error. Reach Lyric technical support at 800-633-3991.
  • 171—Set date and time. Finish these settings so scheduling can occur.
  • 173—Thermostat temperature sensor error. Reach Lyric technical support at 800-633-3991.
  • 175—AC power restarted. No action needed.
  • 181/182—Put in a new air filter. Clear the display by tapping “dismiss” after adding a new filter.
  • 184—Install a new humidifier pad. Clear the monitor by touching “dismiss” after adding a clean pad filter.
  • 185—Put in a new dehumidifier filter. Clear the thermostat by touching “dismiss” after adding a new filter.
  • 187—Clean or install a new ventilator filter. Clear the thermostat by tapping “dismiss” after adding a new filter.
  • 188/189—Replace UV bulb. Call Calverley Service Experts at 817-380-5647 for assistance.
  • 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 exterior temperature. Get the Lyric app to do 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 choose new Wi-Fi network.
  • 508—Wi-Fi not configured. Get the Lyric app and follow the procedure to link your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005)

  • 164—Heat pump requires service. Reach Calverley Service Experts at 817-380-5647 for support.
  • 168—Wi-Fi radio error. Call Calverley Service Experts at 817-380-5647 for support.
  • 170—Internal memory error. Reach Calverley Service Experts at 817-380-5647 for assistance.
  • 171—Set date and time. Finish these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Call Calverley Service Experts at 817-380-5647 for support.
  • 175—AC power restored. No action necessary.
  • 177—Indoor temperature sensor error. Reach Calverley Service Experts at 817-380-5647 for support.
  • 178—Outdoor temperature sensor error. Call Calverley Service Experts at 817-380-5647 for assistance.
  • 181/182—Get a new air filter. Clear the thermostat by tapping “dismiss” after adding a clean filter.
  • 183—Rinse humidifier tank and install a new water filter. Clear the thermostat by touching “dismiss” after finishing these steps.
  • 184—Replace humidifier pad. Clear the monitor by tapping “dismiss” after getting a new pad filter.
  • 185—Get a new dehumidifier filter. Clear the display by tapping “dismiss” after adding a clean filter.
  • 186—Rinse ventilator core. Clear the thermostat by touching “dismiss” after completing this task.
  • 187—Rinse or get a new ventilator filter. Clear the monitor by tapping “dismiss” after installing a new filter.
  • 188/189—Add a new UV bulb. Reach Calverley Service Experts at 817-380-5647 for assistance.
  • 210—Register online for outside temperature. Download the Lyric app to do this step and ensure correct thermostat operation.
  • 388—Register online for remote access and outside temperature. Get the Lyric app to finish 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 choose new Wi-Fi network.
  • 508—Wi-Fi not set up. Get the Lyric app and follow the process to connect your thermostat.

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

Our Experts are Ready to Provide Support

If you’re still experiencing issues after going through the troubleshooting process, our Experts are ready to help. Reach us at 817-380-5647 and we’ll arrive as fast as we can to figure out the problem.

If you have an older thermostat, today is a great time to consider a new device. Thermostat technology has gotten better over the last few years. Ask us for more details on how smart thermostats can make your house better while helping save on heating and cooling expenses throughout the year.

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