How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat manufacturers, and we proudly install them on a regular basis in Houston. They’re long-lasting and reliable. Also, Honeywell is frequently improving its technology, offering more features for your household.

Still, each thermostat can experience errors every so often. That’s why we’ve prepared this useful guide to walk you through troubleshooting.

While you can usually solve the majority of thermostat issues on your own, they occasionally call for Expert support. Our home comfort Experts are available to support you when you need us. We’re just a call away at 713-396-3760.

Let’s get started with the process by determining what type of thermostat your house has.

What Kind of Thermostat Do I Have?

There are three models of thermostats:

  • Manual—This is the older dial-shaped thermostat. You won’t run into error codes with this kind, but it’s also the least efficient for lowering energy bills.
  • Programmable—This thermostat has a digital screen and arrows you press to determine your desired temperature. You can also use daily programs to lower the temperature when you’re gone and set it higher when you come home.
  • Smart—You won’t have to make any programs on this thermostat, as it learns your routine. It intuitively changes the temperature when you or other household members are away to help you save on energy costs. You can also change the temperature anywhere using your phone or other Wi-Fi-enabled device. 

As you know many technologically advanced solutions, there are common malfunctions that might happen. The majority of of these problems don’t need professional help and are simple to solve on your own.

Common Honeywell Thermostat Troubles

All thermostats have a special set of codes that correspond to the problems that take place.

Think how easy it can be to fix a computer by restarting it. In most situations, troubleshooting a thermostat can be just as uncomplicated.

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

Display is Blank

If the monitor is clear on your programmable thermostat, you may need to replace the batteries. If that doesn’t fix the malfunction or you rely on a smart thermostat, there may be a wiring problem.

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

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 cuts off power to the equipment.

Less frequently, a clear display may indicate you will need to get a new thermostat.

Heating and Cooling Equipment Won’t Start

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

During warm weather, verify you put the thermostat lower than the room temperature. When it’s cool, confirm it’s higher. This sounds goofy, but we’ve seen it occur a lot of times.

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

System still won’t start? Make sure circuit breakers haven’t turned off and that your HVAC system isn’t experiencing error codes.

“Cool On” or “Heat On” is Blinking

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

Then, verify it’s calling for the right system to turn on. This is usually indicated by “cool on,” “heat on” or an icon.

If this set of words or the illustration is pulsing, your thermostat is in a five-minute delay state. This feature protects your system from bad short cycling. This may take place if your power is interrupted.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump requires service. Call Church Services at 713-396-3760 for assistance.
  • 168—Wi-Fi radio error. Call Lyric technical support at 800-633-3991. 170—Internal memory error. Contact Lyric technical support at 800-633-3991.
  • 171—Set date and time. Complete these settings so scheduling can run.
  • 173—Thermostat temperature sensor error. Call Lyric technical support at 800-633-3991.
  • 175—AC power restarted. No action required.
  • 181/182—Replace air filter. Clear the monitor by touching “dismiss” after installing a fresh filter.
  • 184—Install a new humidifier pad. Clear the thermostat by hitting “dismiss” after adding a clean pad filter.
  • 185—Put in a new dehumidifier filter. Clear the screen by touching “dismiss” after adding a clean filter.
  • 187—Wash or replace ventilator filter. Clear the thermostat by hitting “dismiss” after adding a clean filter.
  • 188/189—Install a new UV bulb. Ring Church Services at 713-396-3760 for assistance.
  • 210—Register online for outside temperature. Get 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 finish 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 set. Use the Lyric app and follow the process to connect your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump must be serviced service. Reach Church Services at 713-396-3760 for assistance.
  • 168—Wi-Fi radio error. Reach Church Services at 713-396-3760 for assistance.
  • 170—Internal memory error. Reach Church Services at 713-396-3760 for support.
  • 171—Set date and time. Complete these settings so scheduling can operate.
  • 173—Thermostat temperature sensor error. Call Church Services at 713-396-3760 for support.
  • 175—AC power reconnected. No action necessary.
  • 177—Indoor temperature sensor error. Call Church Services at 713-396-3760 for help.
  • 178—Outdoor temperature sensor error. Contact Church Services at 713-396-3760 for help.
  • 181/182—Replace air filter. Clear the display by touching “dismiss” after putting in a fresh filter.
  • 183—Clean humidifier tank and add a new water filter. Clear the display by tapping “dismiss” after finishing these procedures.
  • 184—Install a new humidifier pad. Clear the display by touching “dismiss” after adding a new pad filter.
  • 185—Replace dehumidifier filter. Clear the screen by tapping “dismiss” after adding a new filter.
  • 186—Wash ventilator core. Clear the thermostat by tapping “dismiss” after completing this task.
  • 187—Rinse or install a new ventilator filter. Clear the screen by tapping “dismiss” after buying a new filter.
  • 188/189—Replace UV bulb. Get in touch with Church Services at 713-396-3760 for help.
  • 210—Register online for outdoor temperature. Download the Lyric app to complete this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and exterior 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 pick new Wi-Fi network.
  • 508—Wi-Fi not set up. Download the Lyric app and follow the steps to connect your thermostat.

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

Our Experts are Ready to Provide Support

If you’re still experiencing troubles after working through the troubleshooting steps, our Experts are ready to assist you. Give us a call at 713-396-3760 and we’ll be out rapidly to figure out the problem.

If you rely on an aging thermostat, right now is a fantastic time to think over a replacement. Thermostat technology has come a long way in recent years Ask us for more information on how smart thermostats can make your residence comfier while helping save on heating and cooling costs throughout the year.

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