How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat manufacturers, and we proudly install them on a frequent basis in Sharonville. They’re durable and dependable. In addition, Honeywell is frequently advancing its technology, resulting in more features for your family.

Nevertheless, each thermostat can have errors at times. That’s why we’ve prepared this informative handbook to go over troubleshooting.

While you can often repair the majority of thermostat troubles alone, they occasionally call for Expert assistance. Our heating and cooling Experts are available to support you when you need us. We’re just a call away at 859-905-0834.

Let’s start the process by figuring 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 classic dial-shaped thermostat. You won’t run into error codes with this kind, but it’s also the least efficient for lowering heating and cooling bills.
  • Programmable—This thermostat includes a digital screen and arrows you touch to choose your desired temperature. You can also use daily programs to lower the temperature when you’re away and raise it when you get back.
  • Smart—You won’t have to schedule any programs on this thermostat, because it adjusts to your schedule. It instinctively adjusts the temperature when you or family members are out and about to help you save on energy expenses. You can also raise or lower the temperature anywhere on your phone or other Wi-Fi-enabled device. 

As is the case with most technologically advanced solutions, there are common malfunctions that may take place. Most of these issues don’t require Expert support and are simple to repair alone.

Common Honeywell Thermostat Issues

All thermostats have a special kind of codes that correspond to the glitches that occur.

Think how easy it can be to repair a computer by restarting it. For the most part, troubleshooting a thermostat can be just as uncomplicated.

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

Display is Blank

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

Next, you should make sure the power is flowing for your furnace or air handler. Verify the switch near the indoor equipment is switched “up”.

Also, you should confirm all furnace cabinet or air handler doors/panels are sturdily fastened.

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

While it’s less common, a blank screen can mean you need to replace your thermostat.

Heating and Cooling Equipment Won’t Start

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

When it’s hot, make sure you put the thermostat beneath the ambient temperature. When it’s cool, confirm it’s higher. This sounds goofy, but we’ve seen it take place a lot of times.

Ensure the power switch near your indoor equipment 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 unsecured panel can trip the safety switch, stopping power to the system.

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

“Cool On” or “Heat On” is Flashing

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

Then, check it’s telling the right unit to start. This is typically indicated by “cool on,” “heat on” or an illustration.

If this set of words or the icon is flashing, your thermostat is in a five-minute delay state. This setting keeps your system from bad short cycling. This may take place if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump needs service. Call Knochelmann Service Experts at 859-905-0834 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. Finish these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Call 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 touching “dismiss” after putting in a new filter.
  • 184—Put in a new humidifier pad. Clear the monitor by hitting “dismiss” after adding a fresh pad filter.
  • 185—Replace dehumidifier filter. Clear the screen by touching “dismiss” after installing a new filter.
  • 187—Clean or replace ventilator filter. Clear the thermostat by touching “dismiss” after installing a clean filter.
  • 188/189—Get a new UV bulb. Contact Knochelmann Service Experts at 859-905-0834 for support.
  • 210—Register online for outside 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 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 set up. Get the Lyric app and follow the steps to configure your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump requires service. Reach Knochelmann Service Experts at 859-905-0834 for assistance.
  • 168—Wi-Fi radio error. Call Knochelmann Service Experts at 859-905-0834 for support.
  • 170—Internal memory error. Call Knochelmann Service Experts at 859-905-0834 for assistance.
  • 171—Set date and time. Finalize these settings so scheduling can operate.
  • 173—Thermostat temperature sensor error. Reach Knochelmann Service Experts at 859-905-0834 for help.
  • 175—AC power reconnected. No action needed.
  • 177—Indoor temperature sensor error. Call Knochelmann Service Experts at 859-905-0834 for assistance.
  • 178—Outdoor temperature sensor error. Reach Knochelmann Service Experts at 859-905-0834 for help.
  • 181/182—Install a new air filter. Clear the thermostat by touching “dismiss” after adding a new filter.
  • 183—Clean humidifier tank and install a new water filter. Clear the display by touching “dismiss” after finishing these procedures.
  • 184—Get a new humidifier pad. Clear the thermostat by touching “dismiss” after installing pad filter.
  • 185—Install a new dehumidifier filter. Clear the monitor by hitting “dismiss” after installing a clean filter.
  • 186—Wash ventilator core. Clear the display by touching “dismiss” after completing this task.
  • 187—Rinse or replace ventilator filter. Clear the screen by tapping “dismiss” after buying a new filter.
  • 188/189—Add a new UV bulb. Get in touch with Knochelmann Service Experts at 859-905-0834 for help.
  • 210—Register online for outside temperature. Use the Lyric app to finish this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and outdoor temperature. Get 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 choose new Wi-Fi network.
  • 508—Wi-Fi not set up. Download the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Here to Provide Assistance

If you’re still having problems after working through the troubleshooting steps, our pros are here to assist you. Give us a call at 859-905-0834 and we’ll be out rapidly to figure out the issue.

If you use an aging thermostat, today is a good time to think over a replacement. Thermostat technology has gotten better over the last few years. Ask us for more info on how smart thermostats can make your residence comfier while helping save on utility costs throughout the year.

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