How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the best thermostat manufacturers, and we proudly install them on a regular basis in West Palm Beach. They’re sturdy and reliable. In addition, Honeywell is frequently updating its technology, bringing more features for your house.

Nevertheless, each thermostat can have troubles every so often. Due to this, we’ve prepared this informative guide to go over troubleshooting.

While you can often fix most thermostat troubles alone, they sometimes call for Expert assistance. Our HVAC professionals are ready to support you when you need us. We’re merely a call away at 561-629-1826.

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

What Model 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 one, but it’s also the least efficient for reducing heating and cooling expenses.
  • Programmable—This thermostat includes a digital screen and arrows you touch to choose your desired temperature. You can also choose daily programs to lower 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, as it learns your schedule. It instinctively raises and lowers the temperature when you or family members are out and about to help you save on heating and cooling expenses. You can also change the temperature anywhere on your phone or other Wi-Fi-enabled device. 

As you’re aware the majority of technologically advanced products, there are regular problems that may happen. Many of these issues don’t require pro support and are easy to solve on your own.

Common Honeywell Thermostat Issues

Every thermostat has a unique set of codes that correspond to the glitches that occur.

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

Here is a guide to the most encountered Honeywell thermostat errors. These include the following programmable thermostats:

Display is Blank

If the display is blank on your programmable thermostat, you could need to replace the batteries. If that doesn’t solve the issue or you use a smart thermostat, there might be a wiring issue.

Next, you should ensure the power is on for your furnace or air handler. Confirm the switch near the indoor system is in the “on” position.

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

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

Infrequently, an empty monitor may mean you will need to install a new thermostat.

HVAC Equipment Won’t Start

Check that your thermostat is switched to “cool” or “heat,” not “off.”

In the summer, make sure you put the thermostat beneath the room temperature. When it’s cold, verify it’s higher. This sounds silly, but we’ve seen it take place many times.

Make sure the power switch by your indoor system is in the “on” position. You should also check the cabinet doors or panels are tight on your furnace cabinet or air handler. An open panel can trip the safety switch, diverting power to the system.

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

“Cool On” or “Heat On” is Flickering

First, check your thermostat is on “cool” or “heat.”

Then, make sure it’s signaling the correct system to start. This is often demonstrated by “cool on,” “heat on” or an illustration.

If this phrase or the picture is flashing, your thermostat is in a five-minute delay state. This mode stops your equipment from bad short cycling. This could happen if you lose power.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump requires service. Call Service Experts Heating & Air Conditioning at 561-629-1826 for assistance.
  • 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. Finalize these settings so scheduling can take place.
  • 173—Thermostat temperature sensor error. Reach Lyric technical support at 800-633-3991.
  • 175—AC power resumed. No action required.
  • 181/182—Replace air filter. Clear the display by tapping “dismiss” after putting in a new filter.
  • 184—Install a new humidifier pad. Clear the screen by hitting “dismiss” after adding a clean pad filter.
  • 185—Install a new dehumidifier filter. Clear the thermostat by hitting “dismiss” after adding a fresh filter.
  • 187—Rinse or replace ventilator filter. Clear the screen by tapping “dismiss” after adding a clean filter.
  • 188/189—Replace UV bulb. Ring Service Experts Heating & Air Conditioning at 561-629-1826 for help.
  • 210—Register online for outdoor 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 do this step and ensure accurate 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. Download the Lyric app and follow the procedure to configure your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump requires service. Reach Service Experts Heating & Air Conditioning at 561-629-1826 for support.
  • 168—Wi-Fi radio error. Contact Service Experts Heating & Air Conditioning at 561-629-1826 for support.
  • 170—Internal memory error. Reach Service Experts Heating & Air Conditioning at 561-629-1826 for assistance.
  • 171—Set date and time. Complete these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Reach Service Experts Heating & Air Conditioning at 561-629-1826 for help.
  • 175—AC power restored. No action needed.
  • 177—Indoor temperature sensor error. Call Service Experts Heating & Air Conditioning at 561-629-1826 for support.
  • 178—Outdoor temperature sensor error. Reach Service Experts Heating & Air Conditioning at 561-629-1826 for assistance.
  • 181/182—Replace air filter. Clear the monitor by tapping “dismiss” after installing a clean filter.
  • 183—Clean humidifier tank and add a new water filter. Clear the monitor by tapping “dismiss” after completing these procedures.
  • 184—Install a new humidifier pad. Clear the thermostat by touching “dismiss” after installing pad filter.
  • 185—Install a new dehumidifier filter. Clear the thermostat by tapping “dismiss” after adding a clean filter.
  • 186—Wash ventilator core. Clear the display by hitting “dismiss” after doing this task.
  • 187—Rinse or get a new ventilator filter. Clear the monitor by tapping “dismiss” after getting a new filter.
  • 188/189—Install a new UV bulb. Contact Service Experts Heating & Air Conditioning at 561-629-1826 for support.
  • 210—Register online for outdoor temperature. Download the Lyric app to finish this step and ensure proper thermostat operation.
  • 388—Register online for remote access and outdoor temperature. Download the Lyric app to do 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 connected. Download the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Here to Provide Assistance

If you’re still experiencing problems after going through the troubleshooting list, our professionals are here to help. Give us a call at 561-629-1826 and we’ll come to your house quickly to figure out the problem.

If you use an older thermostat, today is a good time to consider a replacement. Thermostat technology has come a long way lately Ask us for more details on how smart thermostats can make your home more comfortable while helping save on energy bills all year.

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