How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat producers, and we proudly install them on a usual basis in Edmonton. They’re durable and trustworthy. Also, Honeywell is constantly updating its technology, bringing more features for your home.

Nevertheless, all thermostats can run into problems now and then. As a result, we’ve prepared this informative guide to run through troubleshooting.

While you can usually solve the majority of thermostat issues by yourself, they often need Expert assistance. Our heating and cooling professionals are here to support you when you need us. We’re just a call away at 780-800-9047.

Let’s start 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 typical dial-shaped thermostat. You won’t run into error codes with this one, but it’s also the least efficient for reducing utility bills.
  • Programmable—This thermostat includes a digital screen and arrows you use to choose your desired temperature. You can also use daily programs to decrease the temperature when you’re away and increase it when you get back.
  • Smart—You won’t have to schedule any programs on this thermostat, as it learns your routine. It automatically raises and lowers the temperature when you or family members are away to help you save on utility costs. You can also change the temperature anywhere on your phone or other Wi-Fi-enabled device. 

As is the case with the majority of technologically advanced products, there are several glitches that might take place. Many of these issues don’t require pro help and are easy to fix by yourself.

Common Honeywell Thermostat Problems

All thermostats have a unique kind of codes that correspond to the troubles that take place.

Think how uncomplicated it can be to repair a computer by restarting it. In most cases, diagnosing a thermostat can be just as easy.

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

Display is Blank

If the screen is clear on your programmable thermostat, you might need to get new batteries. If that doesn’t fix the malfunction or you have a smart thermostat, there could be a wiring malfunction.

Next, you should ensure the power is flowing for your furnace or air handler. Confirm the switch close to the indoor unit is switched “up”.

Additionally, you should make sure all furnace cabinet or air handler doors/panels are sturdily in place.

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

Less frequently, a blank screen may indicate you should install a new thermostat.

Comfort Unit Won’t Turn On

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

During warm weather, make sure you set the thermostat below the current temperature. When it’s cool, make sure it’s higher. This sounds absurd, but we’ve seen it occur a lot of times.

Ensure the power switch close to your indoor system is in the “on” position. You should also make sure the cabinet doors or panels are tight on your furnace cabinet or air handler. An open panel can activate the safety switch, cutting off current to the unit.

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

“Cool On” or “Heat On” is Blinking

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

Then, verify it’s calling for the appropriate system to turn on. This is usually demonstrated by “cool on,” “heat on” or an icon.

If these words or the icon is flashing, your thermostat is in a five-minute delay status. This mode keeps your system from bad short cycling. This could take place if you lose power.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump requires service. Call Rob's Albertan Service Experts at 780-800-9047 for support.
  • 168—Wi-Fi radio error. Call Lyric technical support at 800-633-3991. 170—Internal memory error. Call Lyric technical support at 800-633-3991.
  • 171—Set date and time. Complete these settings so scheduling can occur.
  • 173—Thermostat temperature sensor error. Reach Lyric technical support at 800-633-3991.
  • 175—AC power restored. No action required.
  • 181/182—Put in a new air filter. Clear the thermostat by touching “dismiss” after putting in a fresh filter.
  • 184—Replace humidifier pad. Clear the thermostat by tapping “dismiss” after putting in a fresh pad filter.
  • 185—Put in a new dehumidifier filter. Clear the display by tapping “dismiss” after installing a clean filter.
  • 187—Rinse or replace ventilator filter. Clear the display by tapping “dismiss” after adding a clean filter.
  • 188/189—Get a new UV bulb. Ring Rob's Albertan Service Experts at 780-800-9047 for support.
  • 210—Register online for exterior temperature. Download the Lyric app to finish this step and ensure correct thermostat operation.
  • 388—Register online for remote access and outdoor temperature. Download the Lyric app to finish this step and ensure correct 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 steps to link your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump requires service. Contact Rob's Albertan Service Experts at 780-800-9047 for support.
  • 168—Wi-Fi radio error. Contact Rob's Albertan Service Experts at 780-800-9047 for help.
  • 170—Internal memory error. Call Rob's Albertan Service Experts at 780-800-9047 for help.
  • 171—Set date and time. Finalize these settings so scheduling can work.
  • 173—Thermostat temperature sensor error. Call Rob's Albertan Service Experts at 780-800-9047 for assistance.
  • 175—AC power restored. No action required.
  • 177—Indoor temperature sensor error. Call Rob's Albertan Service Experts at 780-800-9047 for assistance.
  • 178—Outdoor temperature sensor error. Call Rob's Albertan Service Experts at 780-800-9047 for help.
  • 181/182—Get a new air filter. Clear the screen by tapping “dismiss” after installing a fresh filter.
  • 183—Rinse humidifier tank and add a new water filter. Clear the monitor by hitting “dismiss” after doing these steps.
  • 184—Install a new humidifier pad. Clear the thermostat by tapping “dismiss” after adding a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the thermostat by touching “dismiss” after installing a fresh filter.
  • 186—Clean ventilator core. Clear the display by touching “dismiss” after finishing this task.
  • 187—Clean or get a new ventilator filter. Clear the display by touching “dismiss” after installing a new filter.
  • 188/189—Get a new UV bulb. Get in touch with Rob's Albertan Service Experts at 780-800-9047 for assistance.
  • 210—Register online for outside temperature. Use the Lyric app to do 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 accurate 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 connected. Get the Lyric app and follow the process to connect your thermostat.

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

Our Experts are Here to Provide Support

If you’re still having troubles after working through the troubleshooting steps, our professionals are available to support you. Call us at 780-800-9047 and we’ll come to your house as fast as we can to determine the issue.

If you use an older thermostat, now is a good time to think about a new thermostat. Thermostat technology has advanced in recent years Ask us for more details on how smart thermostats can make your residence more convenient while helping save on energy costs year-round.

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