How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the best thermostat producers, and we proudly install them on a regular basis in London. They’re long-lasting and dependable. In addition, Honeywell is frequently advancing its technology, resulting in more features for your household.

Still, every thermostat can have troubles at one time or another. As a result, we’ve prepared this informative guidebook to run through troubleshooting.

While you can often repair the majority of thermostat troubles by yourself, they occasionally call for Expert help. Our heating and cooling pros are ready to support you when you need us. We’re just a call away at 226-270-1164.

Let’s get started with the process by finding out what model of thermostat your house has.

What Kind of Thermostat Do I Have?

There are three types of thermostats:

  • Manual—This is the classic dial-shaped thermostat. You won’t run into error codes with this one, but it’s also the least efficient for saving on energy bills.
  • Programmable—This thermostat has a digital screen and arrows you touch to set your desired temperature. You can also choose daily programs to reduce the temperature when you’re away and set it higher when you get back.
  • Smart—You won’t have to schedule any programs on this thermostat, since it picks up on your day. It automatically raises and lowers the temperature when you or loved ones are away to help you save on utility expenses. You can also raise or lower the temperature anywhere via your phone or other Wi-Fi-enabled device. 

As you’re aware most technologically advanced products, there are common glitches that may take place. The majority of of these problems don’t call for pro help and are uncomplicated enough to repair by yourself.

Common Honeywell Thermostat Problems

All thermostats have a unique set of codes assigned to the troubles that happen.

Think how simple it can be to fix a computer by restarting it. Many times, correcting a thermostat can be just as simple.

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

Display is Blank

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

Next, you should ensure the power is enabled for your furnace or air handler. Make sure the switch by the indoor equipment is in the “on” position.

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

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

Infrequently, an empty monitor could signify you need to buy a new thermostat.

Heating and Cooling Equipment Won’t Turn On

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

During warm weather, make sure you set the thermostat lower than the current temperature. When it’s cold, confirm it’s higher. This sounds goofy, but we’ve seen it happen lots of times.

Confirm the power switch by your indoor system is in the “on” position. You should also comfirm the cabinet doors or panels are secure on your furnace cabinet or air handler. An open panel can trigger the safety switch, diverting power to the equipment.

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

“Cool On” or “Heat On” is Flickering

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

Then, check it’s telling the appropriate system to run. This is usually shown by “cool on,” “heat on” or an icon.

If these words or the illustration is flashing, your thermostat is in a five-minute delay mode. This setting protects your system from harmful short cycling. This could take place if your power is interrupted.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump needs service. Call Roy Inch & Sons Service Experts at 226-270-1164 for help.
  • 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. Finish these settings so scheduling can take place.
  • 173—Thermostat temperature sensor error. Contact Lyric technical support at 800-633-3991.
  • 175—AC power resumed. No action required.
  • 181/182—Replace air filter. Clear the monitor by tapping “dismiss” after installing a fresh filter.
  • 184—Replace humidifier pad. Clear the thermostat by hitting “dismiss” after putting in a clean pad filter.
  • 185—Put in a new dehumidifier filter. Clear the screen by tapping “dismiss” after putting in a clean filter.
  • 187—Clean or install a new ventilator filter. Clear the monitor by touching “dismiss” after installing a new filter.
  • 188/189—Install a new UV bulb. Contact Roy Inch & Sons Service Experts at 226-270-1164 for assistance.
  • 210—Register online for outdoor 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 do this step and ensure proper thermostat operation.
  • 399—No Internet. Check 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 procedure to link your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump needs service. Reach Roy Inch & Sons Service Experts at 226-270-1164 for assistance.
  • 168—Wi-Fi radio error. Call Roy Inch & Sons Service Experts at 226-270-1164 for help.
  • 170—Internal memory error. Call Roy Inch & Sons Service Experts at 226-270-1164 for assistance.
  • 171—Set date and time. Finish these settings so scheduling can work.
  • 173—Thermostat temperature sensor error. Call Roy Inch & Sons Service Experts at 226-270-1164 for assistance.
  • 175—AC power resumed. No action needed.
  • 177—Indoor temperature sensor error. Reach Roy Inch & Sons Service Experts at 226-270-1164 for assistance.
  • 178—Outdoor temperature sensor error. Reach Roy Inch & Sons Service Experts at 226-270-1164 for help.
  • 181/182—Get a new air filter. Clear the display by tapping “dismiss” after putting in a clean filter.
  • 183—Rinse humidifier tank and add a new water filter. Clear the screen by tapping “dismiss” after doing these tasks.
  • 184—Install a new humidifier pad. Clear the screen by touching “dismiss” after adding a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the screen by hitting “dismiss” after putting in a fresh filter.
  • 186—Rinse ventilator core. Clear the monitor by hitting “dismiss” after finishing this task.
  • 187—Rinse or replace ventilator filter. Clear the monitor by hitting “dismiss” after buying a new filter.
  • 188/189—Add a new UV bulb. Get in touch with Roy Inch & Sons Service Experts at 226-270-1164 for help.
  • 210—Register online for outdoor temperature. Get the Lyric app to complete 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 proper 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 procedures to connect your thermostat.

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

Our Experts are Available to Help

If you’re still experiencing troubles after going through the troubleshooting list, our pros are here to assist you. Call us at 226-270-1164 and we’ll come to your house quickly to diagnose the malfunction.

If you have a dated thermostat, now is a great time to think over a new thermostat. Thermostat technology has come a long way lately Ask us for more details on how smart thermostats can make your home better while helping save on energy bills year-round.

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