How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat producers, and we proudly install them on a regular basis in Calgary. They’re long-lasting and dependable. Also, Honeywell is frequently advancing its technology, offering more features for your family.

Nevertheless, all thermostats can have issues every now and then. Due to this, we’ve put together this informative guidebook to run through troubleshooting.

While you can usually repair most thermostat problems by yourself, they occasionally call for Expert support. Our home comfort professionals are here to support you when you need us. We’re merely a call away at 587-315-5271.

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

What Kind of Thermostat Do I Have?

There are three types of thermostats:

  • Manual—This is the older dial-shaped thermostat. You won’t run into error codes with this kind, but it’s also the least efficient for reducing heating and cooling costs.
  • Programmable—This thermostat features a digital screen and arrows you touch to determine your desired temperature. You can also use daily programs to decrease the temperature when you’re at work and increase it when you return.
  • Smart—You won’t have to schedule any programs on this thermostat, since it picks up on your schedule. It instinctively changes the temperature when you or family members are out and about to help you save on heating and cooling 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 glitches that can take place. Many of these problems don’t require Expert help and are uncomplicated enough to repair 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 problems. These are applicable to the following programmable thermostats:

Display is Blank

If the screen is clear on your programmable thermostat, you could 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 enabled for your furnace or air handler. Confirm 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.

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

Infrequently, a clear 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.”

When it’s hot, make sure 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 happen lots of times.

Make sure the power switch by 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, stopping power to the unit.

System still won’t start? Confirm circuit breakers haven’t turned off and that your HVAC equipment isn’t experiencing error codes.

“Cool On” or “Heat On” is Flickering

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

Then, ensure it’s signaling the correct equipment to run. This is typically shown by “cool on,” “heat on” or an icon.

If this set of words or the illustration is pulsing, your thermostat is in a five-minute delay mode. This mode keeps your unit from harmful short cycling. This may occur if you lose electricity.

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 support.
  • 168—Wi-Fi radio error. Reach 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 take place.
  • 173—Thermostat temperature sensor error. Contact Lyric technical support at 800-633-3991.
  • 175—AC power restarted. No action required.
  • 181/182—Install a new air filter. Clear the monitor by hitting “dismiss” after adding a clean filter.
  • 184—Put in a new humidifier pad. Clear the monitor by hitting “dismiss” after adding a fresh pad filter.
  • 185—Put in a new dehumidifier filter. Clear the screen by hitting “dismiss” after adding a clean filter.
  • 187—Wash or put in a new ventilator filter. Clear the screen 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 exterior 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 select new Wi-Fi network.
  • 508—Wi-Fi not set. Get the Lyric app and follow the process to link 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 help.
  • 170—Internal memory error. Contact A1 Chesney Service Experts at 587-315-5271 for assistance.
  • 171—Set date and time. Finish 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 necessary.
  • 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 tapping “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 tapping “dismiss” after adding 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. Reach A1 Chesney Service Experts at 587-315-5271 for help.
  • 210—Register online for exterior temperature. Use 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 choose new Wi-Fi network.
  • 508—Wi-Fi not set up. Download the Lyric app and follow the process to connect your thermostat.

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

Our Experts are Available to Help

If you’re still experiencing issues after going through the troubleshooting list, our pros are available to assist you. Call us at 587-315-5271 and we’ll be out quickly to determine the problem.

If you have an aging thermostat, right now is a fantastic time to think about 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 throughout the year.

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