How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat manufacturers, and we proudly install them on a frequent basis in Calgary. They’re sturdy and dependable. Plus, Honeywell is frequently advancing its technology, resulting in more features for your house.

Nevertheless, all thermostats can experience errors every now and then. Due to this, we’ve put together this valuable handbook to go over troubleshooting.

While you can typically repair many thermostat troubles by yourself, they occasionally call for Expert assistance. Our home comfort professionals are here to help when you need us. We’re merely a call away at 403-279-5760.

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

What Type 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 reducing heating and cooling costs.
  • Programmable—This thermostat includes a digital screen and arrows you use to set your desired temperature. You can also choose daily programs to decrease the temperature when you’re gone and set it higher when you return.
  • Smart—You won’t have to make any programs on this thermostat, since it learns your schedule. It intuitively adjusts the temperature when you or loved ones are away to help you save on heating and cooling costs. You can also adjust the temperature anywhere on your phone or other Wi-Fi-enabled device. 

As you know the majority of technologically advanced things, there are common problems that can take place. Many of these problems don’t require Expert assistance and are simple to fix by yourself.

Common Honeywell Thermostat Problems

All thermostats have a special group of codes assigned to the problems that take place.

Think how simple it can be to restore a computer by restarting it. In most cases, correcting a thermostat can be just as uncomplicated.

Here are some of the most common Honeywell thermostat issues. These are applicable to the following programmable thermostats:

Display is Blank

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

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

In addition to that, you should make sure all furnace cabinet or air handler doors/panels are securely in place.

A loose panel may trip the safety switch, which cuts off power to the system.

Infrequently, a clear display may signify you will need to get a new thermostat.

Comfort Unit Won’t Start

Ensure that your thermostat is on “cool” or “heat,” not “off.”

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

Confirm the power switch close to 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. A loose panel can activate the safety switch, diverting power to the unit.

Equipment still won’t turn on? Confirm circuit breakers haven’t flipped and that your HVAC system isn’t experiencing error codes.

“Cool On” or “Heat On” is Flashing

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

Then, verify it’s calling for the correct system to run. This is usually indicated by “cool on,” “heat on” or a picture.

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

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump needs service. Call Service Experts Heating & Air Conditioning at 403-279-5760 for support.
  • 168—Wi-Fi radio error. Contact 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 restored. No action necessary.
  • 181/182—Install a new air filter. Clear the thermostat by hitting “dismiss” after installing a clean filter.
  • 184—Put in a new humidifier pad. Clear the display by tapping “dismiss” after putting in a fresh 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 screen by touching “dismiss” after installing a new filter.
  • 188/189—Get a new UV bulb. Contact Service Experts Heating & Air Conditioning at 403-279-5760 for help.
  • 210—Register online for exterior temperature. Get the Lyric app to complete this step and ensure proper thermostat operation.
  • 388—Register online for remote access and exterior temperature. Use the Lyric app to finish 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. Get the Lyric app and follow the steps to configure your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump needs service. Reach Service Experts Heating & Air Conditioning at 403-279-5760 for help.
  • 168—Wi-Fi radio error. Contact Service Experts Heating & Air Conditioning at 403-279-5760 for support.
  • 170—Internal memory error. Call Service Experts Heating & Air Conditioning at 403-279-5760 for support.
  • 171—Set date and time. Complete these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Contact Service Experts Heating & Air Conditioning at 403-279-5760 for assistance.
  • 175—AC power reconnected. No action necessary.
  • 177—Indoor temperature sensor error. Call Service Experts Heating & Air Conditioning at 403-279-5760 for assistance.
  • 178—Outdoor temperature sensor error. Contact Service Experts Heating & Air Conditioning at 403-279-5760 for assistance.
  • 181/182—Replace air filter. Clear the display by tapping “dismiss” after adding a clean filter.
  • 183—Rinse humidifier tank and replace water filter. Clear the thermostat by tapping “dismiss” after doing these procedures.
  • 184—Replace humidifier pad. Clear the thermostat by touching “dismiss” after installing pad filter.
  • 185—Get a new dehumidifier filter. Clear the display by touching “dismiss” after installing a new filter.
  • 186—Rinse ventilator core. Clear the thermostat by hitting “dismiss” after completing this task.
  • 187—Clean or replace ventilator filter. Clear the monitor by touching “dismiss” after buying a new filter.
  • 188/189—Replace UV bulb. Contact Service Experts Heating & Air Conditioning at 403-279-5760 for support.
  • 210—Register online for outdoor temperature. Get the Lyric app to finish this step and ensure correct thermostat operation.
  • 388—Register online for remote access and exterior temperature. Download the Lyric app to finish 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 select new Wi-Fi network.
  • 508—Wi-Fi not connected. Use the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Available to Help

If you’re still experiencing issues after going through the troubleshooting list, our professionals are ready to support you. Call us at 403-279-5760 and we’ll come to your house quickly to diagnose the problem.

If you rely on an aging thermostat, right now is a fantastic time to consider a replacement. Thermostat technology has gotten better lately Ask us for more info on how smart thermostats can make your house more convenient while helping save on heating and cooling expenses year-round.

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