How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the top thermostat producers, and we proudly install them on a regular basis in La Porte. They’re long-lasting and reliable. Plus, Honeywell is regularly updating its technology, resulting in more features for your family.

Nevertheless, all thermostats can run into troubles at one time or another. That’s why we’ve prepared this useful guidebook to go over troubleshooting.

While you can usually solve the majority of thermostat issues alone, they occasionally require Expert help. Our heating and cooling Experts are ready to help when you need us. We’re merely a call away at 281-407-9478.

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

What Kind of Thermostat Do I Have?

There are three models of thermostats:

  • Manual—This is the classic dial-shaped thermostat. You won’t experience error codes with this type, but it’s also the least efficient for lowering heating and cooling bills.
  • Programmable—This thermostat has a digital screen and arrows you press to choose your desired temperature. You can also choose daily programs to reduce the temperature when you’re away and increase it when you get back.
  • Smart—You won’t have to set any programs on this thermostat, since it picks up on your routine. It instinctively adjusts 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 know the majority of technologically advanced things, there are regular glitches that may take place. Many of these situations don’t need pro help and are uncomplicated enough to repair on your own.

Common Honeywell Thermostat Troubles

All thermostats have an exclusive kind of codes assigned to the problems that happen.

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

Here is a listing the most common Honeywell thermostat errors. These involve the following programmable thermostats:

Display is Blank

If the monitor is clear on your programmable thermostat, you might need to put in new batteries. If that doesn’t fix the problem or you use a smart thermostat, there could be a wiring malfunction.

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

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

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

Less frequently, a clear monitor might mean you need to install a new thermostat.

Comfort Unit Won’t Run

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

During warm weather, confirm you put the thermostat lower than the current temperature. In the winter, make sure it’s higher. This sounds silly, but we’ve seen it happen many times.

Confirm the power switch close to your indoor equipment is in the “on” position. You should also check the cabinet doors or panels are secure on your furnace cabinet or air handler. An unsecured panel can activate the safety switch, stopping electricity to the equipment.

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

“Cool On” or “Heat On” is Blinking

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

Then, check it’s calling for the correct equipment to start. This is often shown by “cool on,” “heat on” or a picture.

If this set of words or the icon is flashing, your thermostat is in a five-minute delay mode. This setting protects your unit 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 Finch Air Conditioning & Heating at 281-407-9478 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. Finish these settings so scheduling can occur.
  • 173—Thermostat temperature sensor error. Contact Lyric technical support at 800-633-3991.
  • 175—AC power restarted. No action necessary.
  • 181/182—Put in a new air filter. Clear the monitor by tapping “dismiss” after putting in a clean filter.
  • 184—Put in a new humidifier pad. Clear the monitor by tapping “dismiss” after installing a clean pad filter.
  • 185—Put in a new dehumidifier filter. Clear the thermostat by touching “dismiss” after putting in a clean filter.
  • 187—Wash or replace ventilator filter. Clear the thermostat by hitting “dismiss” after putting in a clean filter.
  • 188/189—Install a new UV bulb. Call Finch Air Conditioning & Heating at 281-407-9478 for help.
  • 210—Register online for outdoor temperature. Download the Lyric app to finish 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 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 set up. Get the Lyric app and follow the procedure to connect your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005) 

  • 164—Heat pump needs service. Contact Finch Air Conditioning & Heating at 281-407-9478 for support.
  • 168—Wi-Fi radio error. Call Finch Air Conditioning & Heating at 281-407-9478 for help.
  • 170—Internal memory error. Call Finch Air Conditioning & Heating at 281-407-9478 for help.
  • 171—Set date and time. Finalize these settings so scheduling can work.
  • 173—Thermostat temperature sensor error. Call Finch Air Conditioning & Heating at 281-407-9478 for assistance.
  • 175—AC power resumed. No action needed.
  • 177—Indoor temperature sensor error. Reach Finch Air Conditioning & Heating at 281-407-9478 for assistance.
  • 178—Outdoor temperature sensor error. Call Finch Air Conditioning & Heating at 281-407-9478 for support.
  • 181/182—Install a new air filter. Clear the monitor by tapping “dismiss” after adding a clean filter.
  • 183—Rinse humidifier tank and replace water filter. Clear the monitor by hitting “dismiss” after finishing these procedures.
  • 184—Replace humidifier pad. Clear the display by tapping “dismiss” after adding a new pad filter.
  • 185—Install a new dehumidifier filter. Clear the monitor by tapping “dismiss” after adding a fresh filter.
  • 186—Wash ventilator core. Clear the monitor by touching “dismiss” after finishing this task.
  • 187—Wash or install a new ventilator filter. Clear the display by hitting “dismiss” after getting a new filter.
  • 188/189—Get a new UV bulb. Get in touch with Finch Air Conditioning & Heating at 281-407-9478 for help.
  • 210—Register online for exterior temperature. Download the Lyric app to finish this step and ensure accurate thermostat operation.
  • 388—Register online for remote access and exterior temperature. Download the Lyric app to complete 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 connected. Download the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Available to Provide Assistance

If you’re still experiencing problems after working through the troubleshooting process, our pros are ready to help. Call us at 281-407-9478 and we’ll be out as fast as we can to diagnose the problem.

If you have an older thermostat, right now is a fantastic time to consider a new device. Thermostat technology has come a long way in recent years Ask us for more information on how smart thermostats can make your home comfier while helping save on energy costs all year.

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