How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat producers, and we proudly install them on a frequent basis in Fort Lauderdale. They’re durable and trustworthy. Plus, Honeywell is regularly updating its technology, bringing more features for your household.

However, every thermostat can have problems every now and then. Due to this, we’ve put together this helpful guide to run through troubleshooting. While Honeywell thermostat problems are rare, they do occur. 

While you can typically fix the majority of thermostat issues by yourself, they sometimes need Expert help. Our heating and cooling professionals are here to support you when you need us. We’re merely a call away at 954-736-4314.

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

What Type of Thermostat Do I Have?

There are three kinds of thermostats:

  • Manual—This is the typical dial-shaped thermostat. You won’t experience error codes with this kind, but it’s also the least efficient for reducing heating and cooling bills.
  • Programmable—This thermostat includes a digital screen and arrows you touch to set your desired temperature. You can also set daily programs to decrease the temperature when you’re gone and raise it when you return.
  • Smart—You won’t have to schedule any programs on this thermostat, since it learns your routine. It automatically adjusts the temperature when you or family members are gone to help you save on utility costs. You can also change the temperature anywhere via your phone or other Wi-Fi-enabled device. 

As you’re aware the majority of technologically advanced solutions, there are common malfunctions that can happen. The majority of of these problems don’t call for pro assistance and are uncomplicated enough to repair by yourself.

Common Honeywell Thermostat Troubles

All thermostats have a special group of codes that correspond to the glitches that take place.

Think how simple it can be to fix a computer by restarting it. In many instances, diagnosing a thermostat can be just as simple.

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

Display is Blank

If the monitor is empty on your programmable thermostat, you may need to replace the batteries. If that doesn’t take care of the issue or you use a smart thermostat, there may be a wiring issue.

Next, you should check the power is flowing for your furnace or air handler. Confirm the switch by the indoor equipment is switched “up”.

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

An unsecured panel may trip the safety switch, which cuts off power to the equipment.

Less frequently, an empty screen can signify you need to buy a new thermostat.

HVAC System Won’t Work

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

When it’s hot, confirm you schedule the thermostat lower than the current temperature. In the winter, verify it’s higher. This sounds goofy, but we’ve seen it happen many times.

Confirm the power switch near 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. A loose panel can activate the safety switch, stopping electricity to the system.

Heating or cooling still won’t run? Verify circuit breakers haven’t flipped and that your HVAC system isn’t displaying error codes.

“Cool On” or “Heat On” is Flashing

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

Then, check it’s telling the appropriate unit to start. This is typically demonstrated by “cool on,” “heat on” or an icon.

If this phrase or the picture is blinking, your thermostat is in a five-minute delay status. This mode protects your unit from damaging short cycling. This may occur if your power is interrupted.

Honeywell Thermostat-Specific Error Codes

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

  • 164—Heat pump needs service. Call Service Experts Heating & Air Conditioning at 954-736-4314 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 run.
  • 173—Thermostat temperature sensor error. Contact Lyric technical support at 800-633-3991.
  • 175—AC power restored. No action required.
  • 181/182—Put in a new air filter. Clear the thermostat by hitting “dismiss” after installing a fresh filter.
  • 184—Install a new humidifier pad. Clear the monitor by hitting “dismiss” after installing a fresh pad filter.
  • 185—Put in a new dehumidifier filter. Clear the thermostat by hitting “dismiss” after installing a new filter.
  • 187—Rinse or put in a new ventilator filter. Clear the monitor by touching “dismiss” after adding a new filter.
  • 188/189—Get a new UV bulb. Call Service Experts Heating & Air Conditioning at 954-736-4314 for assistance.
  • 210—Register online for outdoor temperature. Get the Lyric app to finish this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and exterior temperature. Use the Lyric app to finish 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 select new Wi-Fi network.
  • 508—Wi-Fi not configured. Get the Lyric app and follow the process to connect your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump requires service. Contact Service Experts Heating & Air Conditioning at 954-736-4314 for support.
  • 168—Wi-Fi radio error. Reach Service Experts Heating & Air Conditioning at 954-736-4314 for assistance.
  • 170—Internal memory error. Contact Service Experts Heating & Air Conditioning at 954-736-4314 for help.
  • 171—Set date and time. Finish these settings so scheduling can operate.
  • 173—Thermostat temperature sensor error. Contact Service Experts Heating & Air Conditioning at 954-736-4314 for assistance.
  • 175—AC power reconnected. No action required.
  • 177—Indoor temperature sensor error. Call Service Experts Heating & Air Conditioning at 954-736-4314 for support.
  • 178—Outdoor temperature sensor error. Reach Service Experts Heating & Air Conditioning at 954-736-4314 for help.
  • 181/182—Get a new air filter. Clear the thermostat by touching “dismiss” after installing a fresh filter.
  • 183—Rinse humidifier tank and replace water filter. Clear the monitor by tapping “dismiss” after finishing these steps.
  • 184—Replace humidifier pad. Clear the monitor by touching “dismiss” after installing pad filter.
  • 185—Replace dehumidifier filter. Clear the screen by tapping “dismiss” after installing a clean filter.
  • 186—Clean ventilator core. Clear the screen by touching “dismiss” after finishing this task.
  • 187—Clean or replace ventilator filter. Clear the display by tapping “dismiss” after buying a new filter.
  • 188/189—Add a new UV bulb. Reach Service Experts Heating & Air Conditioning at 954-736-4314 for help.
  • 210—Register online for outside temperature. Download the Lyric app to do this step and ensure proper thermostat operation.
  • 388—Register online for remote access and outdoor temperature. Use the Lyric app to complete this step and ensure proper thermostat operation.
  • 399—No Internet. Confirm 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. Use the Lyric app and follow the steps to connect your thermostat.

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

Our Experts are Ready to Provide Assistance

If you’re still experiencing issues after going through the troubleshooting steps, our Experts are available to support you. Call us at 954-736-4314 and we’ll come to your house rapidly to diagnose the problem.

If you have a dated thermostat, today is a great time to consider a new device. Thermostat technology has come a long way over the last few years. Ask us for more details on how smart thermostats can make your residence comfier while helping save on energy costs year-round.

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