How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat producers, and we proudly install them on a frequent basis in Calgary. They’re sturdy and dependable. Also, Honeywell is frequently enhancing its technology, offering more features for your family.

Nevertheless, all thermostats can have issues occasionally. As a result, we’ve put together this helpful guidebook to run through troubleshooting.

While you can usually solve most thermostat problems by yourself, they occasionally call for Expert support. Our HVAC professionals are available to support you when you need us. We’re just a call away at 587-315-5271.

Let’s begin the process by determining what kind of thermostat your home has.

What Kind of Thermostat Do I Have?

There are three types of thermostats:

  • Manual—This is the typical dial-shaped thermostat. You won’t run into error codes with this type, 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 use daily programs to decrease the temperature when you’re at work and set it higher when you get back.
  • Smart—You won’t have to schedule any programs on this thermostat, since it adjusts to your schedule. It instinctively changes the temperature when you or loved ones are out and about to help you save on energy bills. You can also raise or lower the temperature anywhere via your phone or other Wi-Fi-enabled device. 

As is the case with the majority of technologically advanced things, there are regular malfunctions that can happen. Many of these problems don’t require Expert help and are simple to solve alone.

Common Honeywell Thermostat Problems

Each thermostat has an exclusive kind of codes assigned to the malfunctions that occur.

Think how easy it can be to fix a computer by restarting it. In many instances, troubleshooting a thermostat can be just as simple.

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

Display is Blank

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

Next, you should make sure the power is flowing for your furnace or air handler. Verify the switch near the indoor unit is switched “on”.

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

An unsecured panel may trip the safety switch, which cuts off power to the unit.

Infrequently, an empty screen may mean you should replace your thermostat.

Comfort System Won’t Run

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

During warm weather, make sure you set the thermostat lower than the ambient temperature. When it’s cool, verify it’s higher. This sounds silly, but we’ve seen it happen a lot of times.

Make sure the power switch close to your indoor system 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 unsecured panel can activate the safety switch, stopping power to the unit.

Unit still won’t start? Confirm circuit breakers haven’t flipped and that your HVAC equipment isn’t showing error codes.

“Cool On” or “Heat On” is Blinking

First, ensure your thermostat is switched to “cool” or “heat.”

Then, ensure it’s telling the correct equipment to run. This is often demonstrated by “cool on,” “heat on” or an icon.

If this phrase or the illustration is pulsing, your thermostat is in a five-minute delay mode. This mode stops your equipment from harmful short cycling. This could occur if your power is interrupted.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump must be serviced. Call A1 Chesney Service Experts at 587-315-5271 for help.
  • 168—Wi-Fi radio error. Reach Lyric technical support at 800-633-3991. 170—Internal memory error. Reach Lyric technical support at 800-633-3991.
  • 171—Set date and time. Complete these settings so scheduling can take place.
  • 173—Thermostat temperature sensor error. Contact Lyric technical support at 800-633-3991.
  • 175—AC power restarted. No action required.
  • 181/182—Put in a new air filter. Clear the monitor by hitting “dismiss” after putting in a clean filter.
  • 184—Install a new humidifier pad. Clear the monitor by hitting “dismiss” after putting in a clean pad filter.
  • 185—Install a new dehumidifier filter. Clear the screen by hitting “dismiss” after putting in a clean filter.
  • 187—Wash or put in a new ventilator filter. Clear the monitor by tapping “dismiss” after installing a fresh filter.
  • 188/189—Get a new UV bulb. Ring A1 Chesney Service Experts at 587-315-5271 for assistance.
  • 210—Register online for exterior temperature. Get 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 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 select new Wi-Fi network.
  • 508—Wi-Fi not set up. Use the Lyric app and follow the procedure to configure your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump needs service. Call A1 Chesney Service Experts at 587-315-5271 for support.
  • 168—Wi-Fi radio error. Contact A1 Chesney Service Experts at 587-315-5271 for support.
  • 170—Internal memory error. Contact A1 Chesney Service Experts at 587-315-5271 for assistance.
  • 171—Set date and time. Finalize these settings so scheduling can operate.
  • 173—Thermostat temperature sensor error. Contact A1 Chesney Service Experts at 587-315-5271 for assistance.
  • 175—AC power resumed. No action needed.
  • 177—Indoor temperature sensor error. Call A1 Chesney Service Experts at 587-315-5271 for assistance.
  • 178—Outdoor temperature sensor error. Call A1 Chesney Service Experts at 587-315-5271 for support.
  • 181/182—Replace air filter. Clear the display by hitting “dismiss” after putting in a new filter.
  • 183—Wash humidifier tank and replace water filter. Clear the thermostat by touching “dismiss” after completing these procedures.
  • 184—Replace humidifier pad. Clear the thermostat by hitting “dismiss” after getting a new pad filter.
  • 185—Replace dehumidifier filter. Clear the screen by hitting “dismiss” after installing a fresh filter.
  • 186—Clean ventilator core. Clear the thermostat by tapping “dismiss” after finishing this task.
  • 187—Clean or replace ventilator filter. Clear the display by touching “dismiss” after buying a new filter.
  • 188/189—Add a new UV bulb. Get in touch with A1 Chesney Service Experts at 587-315-5271 for help.
  • 210—Register online for exterior temperature. Get the Lyric app to do this step and ensure proper thermostat operation.
  • 388—Register online for remote access and outside temperature. Download the Lyric app to do 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 procedures to connect your thermostat.

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

Our Experts are Available to Help

If you’re still running into troubles after trying the troubleshooting list, our pros are available to support you. Reach us at 587-315-5271 and we’ll be out quickly to determine the problem.

If you have a dated thermostat, today is a great time to think over a new thermostat. Thermostat technology has come a long way in recent years Ask us for more info on how smart thermostats can make your residence more convenient while helping save on heating and cooling costs all year.

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