How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat producers, and we proudly install them on a usual basis in East Syracuse. They’re long-lasting and trustworthy. Also, Honeywell is constantly advancing its technology, bringing more features for your residence.

However, each thermostat can experience problems every now and then. As a result, we’ve prepared this helpful guidebook to go over troubleshooting.

While you can usually repair the majority of thermostat troubles on your own, they sometimes require Expert help. Our HVAC pros are available to support you when you need us. We’re only a call away at 315-313-6531.

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

What Kind of Thermostat Do I Have?

There are three kinds of thermostats:

  • Manual—This is the older dial-shaped thermostat. You won’t experience error codes with this kind, but it’s also the least efficient for reducing energy expenses.
  • Programmable—This thermostat features a digital screen and arrows you touch to determine your desired temperature. You can also set daily programs to lower the temperature when you’re at work and set it higher when you get back.
  • Smart—You won’t have to set any programs on this thermostat, as it picks up on your schedule. It instinctively adjusts the temperature when you or loved ones are gone to help you save on energy expenses. You can also adjust the temperature anywhere using your phone or other Wi-Fi-enabled device. 

As you’re aware the majority of technologically advanced things, there are regular problems that can take place. Most of these issues don’t need Expert support and are simple to repair by yourself.

Common Honeywell Thermostat Issues

Each thermostat has an exclusive kind of codes assigned to the problems that happen.

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

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

Display is Blank

If the monitor is blank on your programmable thermostat, you could need to put in new batteries. If that doesn’t solve the problem or you use a smart thermostat, there may be a wiring malfunction.

Next, you should ensure the power is on for your furnace or air handler. Verify the switch near 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 tightly fastened.

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

While it’s less common, an empty screen could mean you should install a new thermostat.

Heating and Cooling Unit Won’t Work

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

When it’s hot, make sure you schedule the thermostat below the ambient temperature. When it’s cool, verify it’s higher. This sounds goofy, but we’ve seen it occur a lot of times.

Make sure the power switch by your indoor unit 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 current to the equipment.

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

“Cool On” or “Heat On” is Blinking

To start, verify your thermostat is on “cool” or “heat.”

Then, check it’s calling for the appropriate equipment to start. This is often demonstrated by “cool on,” “heat on” or an icon.

If this set of words or the picture is pulsing, your thermostat is in a five-minute delay state. This setting keeps your unit from harmful short cycling. This can take place if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump requires service. Call Falso Service Experts at 315-313-6531 for assistance.
  • 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. Finalize these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Reach Lyric technical support at 800-633-3991.
  • 175—AC power resumed. No action necessary.
  • 181/182—Put in a new air filter. Clear the display by hitting “dismiss” after putting in a fresh filter.
  • 184—Put in a new humidifier pad. Clear the monitor by tapping “dismiss” after putting in a clean pad filter.
  • 185—Install a new dehumidifier filter. Clear the monitor by tapping “dismiss” after putting in a clean filter.
  • 187—Rinse or install a new ventilator filter. Clear the thermostat by tapping “dismiss” after adding a new filter.
  • 188/189—Install a new UV bulb. Contact Falso Service Experts at 315-313-6531 for help.
  • 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 exterior temperature. Get the Lyric app to finish this step and ensure proper thermostat operation.
  • 399—No Internet. Confirm your network settings.
  • 400—No Wi-Fi signal. Wait for the thermostat to reconnect or pick new Wi-Fi network.
  • 508—Wi-Fi not configured. Get the Lyric app and follow the process to configure your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump must be serviced service. Call Falso Service Experts at 315-313-6531 for support.
  • 168—Wi-Fi radio error. Reach Falso Service Experts at 315-313-6531 for help.
  • 170—Internal memory error. Call Falso Service Experts at 315-313-6531 for support.
  • 171—Set date and time. Complete these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Call Falso Service Experts at 315-313-6531 for assistance.
  • 175—AC power resumed. No action needed.
  • 177—Indoor temperature sensor error. Contact Falso Service Experts at 315-313-6531 for assistance.
  • 178—Outdoor temperature sensor error. Reach Falso Service Experts at 315-313-6531 for assistance.
  • 181/182—Install a new air filter. Clear the thermostat by tapping “dismiss” after installing a new filter.
  • 183—Rinse humidifier tank and add a new water filter. Clear the thermostat by hitting “dismiss” after finishing these procedures.
  • 184—Install a new humidifier pad. Clear the thermostat by touching “dismiss” after installing pad filter.
  • 185—Replace dehumidifier filter. Clear the thermostat by touching “dismiss” after putting in a clean filter.
  • 186—Wash ventilator core. Clear the screen by touching “dismiss” after completing this task.
  • 187—Wash or get a new ventilator filter. Clear the display by tapping “dismiss” after installing a new filter.
  • 188/189—Get a new UV bulb. Get in touch with Falso Service Experts at 315-313-6531 for help.
  • 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 exterior temperature. Use the Lyric app to complete 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 connected. Use 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 Help

If you’re still having issues after trying the troubleshooting steps, our professionals are ready to help. Give us a call at 315-313-6531 and we’ll arrive rapidly to determine the problem.

If you rely on a dated thermostat, right now is a great time to consider a replacement. Thermostat technology has gotten better in recent years Ask us for more information on how smart thermostats can make your residence comfier while helping save on energy bills year-round.

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