How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat producers, and we proudly install them on a regular basis in Atlanta. They’re durable and dependable. In addition, Honeywell is constantly updating its technology, resulting in more features for your residence.

Still, each thermostat can have issues once in awhile. As a result, we’ve prepared this useful guide to go over troubleshooting. While Honeywell thermostat problems are rare, they happen. 

While you can usually repair the majority of thermostat troubles on your own, they occasionally require Expert support. Our heating and cooling pros are here to assist you when you need us. We’re merely a call away at 678-235-9699.

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 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 saving on heating and cooling expenses.
  • Programmable—This thermostat has a digital screen and arrows you touch to determine your desired temperature. You can also use daily programs to reduce the temperature when you’re at work and increase it when you come home.
  • Smart—You won’t have to schedule any programs on this thermostat, because it learns your day. It instinctively adjusts the temperature when you or family members are gone to help you save on utility bills. You can also change the temperature anywhere on your phone or other Wi-Fi-enabled device. 

As you’re aware many technologically advanced solutions, there are common problems that may occur. The majority of of these troubles don’t need Expert assistance and are simple to repair on your own.

Common Honeywell Thermostat Troubles

Each thermostat has an exclusive kind of codes matching the troubles that take place.

Think how uncomplicated it can be to restore a computer by restarting it. In many instances, diagnosing a thermostat can be just as easy.

Here is a listing the most common Honeywell thermostat problems. These apply to the following programmable thermostats:

Display is Blank

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

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

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

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

Less frequently, a clear monitor can indicate you will need to buy a new thermostat.

Comfort Equipment Won’t Run

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

During warm weather, make sure you schedule the thermostat below the current temperature. In the winter, verify it’s higher. This sounds absurd, but we’ve seen it occur lots of times.

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

Heating or cooling still won’t run? Make sure circuit breakers haven’t tripped and that your HVAC unit isn’t experiencing error codes.

“Cool On” or “Heat On” is Flickering

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

Then, check it’s signaling the appropriate unit to turn on. This is often indicated by “cool on,” “heat on” or an icon.

If these words or the picture is pulsing, your thermostat is in a five-minute delay status. This mode stops your system from harmful short cycling. This can 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 Peachtree Service Experts at 678-235-9699 for help.
  • 168—Wi-Fi radio error. Reach Lyric technical support at 800-633-3991. 170—Internal memory error. Call Lyric technical support at 800-633-3991.
  • 171—Set date and time. Finalize these settings so scheduling can occur.
  • 173—Thermostat temperature sensor error. Contact Lyric technical support at 800-633-3991.
  • 175—AC power restarted. No action necessary.
  • 181/182—Put in a new air filter. Clear the screen by touching “dismiss” after installing a new filter.
  • 184—Install a new humidifier pad. Clear the thermostat by tapping “dismiss” after putting in a new pad filter.
  • 185—Replace dehumidifier filter. Clear the thermostat by tapping “dismiss” after putting in a new filter.
  • 187—Rinse or replace ventilator filter. Clear the monitor by tapping “dismiss” after adding a fresh filter.
  • 188/189—Get a new UV bulb. Contact Peachtree Service Experts at 678-235-9699 for support.
  • 210—Register online for outside temperature. Get the Lyric app to complete this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and outdoor temperature. Use the Lyric app to complete this step and ensure correct thermostat operation.
  • 399—No Internet. Check 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 procedure to configure your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump requires service. Reach Peachtree Service Experts at 678-235-9699 for help.
  • 168—Wi-Fi radio error. Reach Peachtree Service Experts at 678-235-9699 for support.
  • 170—Internal memory error. Contact Peachtree Service Experts at 678-235-9699 for support.
  • 171—Set date and time. Finalize these settings so scheduling can work.
  • 173—Thermostat temperature sensor error. Call Peachtree Service Experts at 678-235-9699 for support.
  • 175—AC power reconnected. No action required.
  • 177—Indoor temperature sensor error. Contact Peachtree Service Experts at 678-235-9699 for support.
  • 178—Outdoor temperature sensor error. Call Peachtree Service Experts at 678-235-9699 for help.
  • 181/182—Replace air filter. Clear the screen by touching “dismiss” after adding a new filter.
  • 183—Rinse humidifier tank and add a new water filter. Clear the monitor by hitting “dismiss” after finishing these steps.
  • 184—Get a new humidifier pad. Clear the screen by hitting “dismiss” after getting a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the thermostat by tapping “dismiss” after adding a new filter.
  • 186—Wash ventilator core. Clear the monitor by tapping “dismiss” after doing this task.
  • 187—Rinse or install a new ventilator filter. Clear the monitor by touching “dismiss” after installing a new filter.
  • 188/189—Install a new UV bulb. Reach Peachtree Service Experts at 678-235-9699 for help.
  • 210—Register online for exterior temperature. Use 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 complete 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 configured. Use the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Ready to Provide Assistance

If you’re still experiencing problems after trying the troubleshooting steps, our pros are ready to help. Give us a call at 678-235-9699 and we’ll come to your house as fast as we can to diagnose the issue.

If you rely on an aging thermostat, today is a fantastic time to consider a replacement. Thermostat technology has advanced in recent years Ask us for more details on how smart thermostats can make your residence comfier while helping save on utility costs year-round.

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