How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the best thermostat manufacturers, and we proudly install them on a frequent basis in Edmonton. They’re long-lasting and trustworthy. Plus, Honeywell is constantly improving its technology, bringing more features for your residence.

Still, all thermostats can run into problems every now and then. That’s why we’ve put together this valuable guide to walk you through troubleshooting. While Honeywell thermostat troubleshooting problems are rare, they happen.

While you can often fix most thermostat problems alone, they sometimes need Expert support. Our heating and cooling Experts are ready to help when you need us. We’re only a call away at 587-404-0790.

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

What Kind of Thermostat Do I Have?

There are three types of thermostats:

Manual—This is the typical dial-shaped thermostat. You won’t run into error codes with this kind, but it’s also the least efficient for lowering energy costs.
Programmable—This thermostat includes a digital screen and arrows you press to choose your desired temperature. You can also use daily programs to lower the temperature when you’re at work and increase it when you get back.
Smart—You won’t have to schedule any programs on this thermostat, since it picks up on your day. It instinctively raises and lowers the temperature when you or loved ones are out and about to help you save on heating and cooling bills. You can also raise or lower the temperature anywhere using your phone or other Wi-Fi-enabled device.

As you’re aware the majority of technologically advanced things, there are common glitches that may occur. The majority of of these troubles don’t call for professional help and are simple to solve on your own.

Common Honeywell Thermostat Troubleshooting Issues

Every Honeywell thermostat has an exclusive set of codes assigned to the problems that take place.

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

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

Display is Blank

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

Next, you should check the power is flowing for your furnace or air handler. Make sure the switch near the indoor system is switched “on”.

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

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

Less frequently, a clear display can indicate you need to replace your thermostat.

Comfort Unit Won’t Start

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

When it’s hot, verify you put the thermostat beneath the ambient temperature. When it’s cool, verify it’s higher. This sounds silly, but we’ve seen it occur lots of times.

Confirm the power switch by your indoor unit 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 trigger the safety switch, cutting off power to the system.

Heating or cooling still won’t turn on? Make sure circuit breakers haven’t turned off and that your HVAC unit isn’t displaying error codes.

“Cool On” or “Heat On” is Flashing

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

Then, make sure it’s telling the right equipment to run. This is typically shown by “cool on,” “heat on” or an icon.

If these words or the icon is blinking, your thermostat is in a five-minute delay province. This feature keeps your equipment from bad short cycling. This can occur if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

164—Heat pump requires service. Call Service Experts Heating & Air Conditioning at 587-404-0790 for assistance.
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. Finalize these settings so scheduling can run.
173—Thermostat temperature sensor error. Call Lyric technical support at 800-633-3991.
175—AC power resumed. No action necessary.
181/182—Replace air filter. Clear the screen by tapping “dismiss” after adding a new filter.
184—Replace humidifier pad. Clear the screen by tapping “dismiss” after putting in a fresh pad filter.
185—Install a new dehumidifier filter. Clear the monitor by tapping “dismiss” after adding a fresh filter.
187—Rinse or replace ventilator filter. Clear the display by touching “dismiss” after adding a new filter.
188/189—Replace UV bulb. Call Service Experts Heating & Air Conditioning at 587-404-0790 for support.
210—Register online for outdoor temperature. Use the Lyric app to complete this step and ensure accurate thermostat operation.
388—Register online for remote access and outside 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 set. Get the Lyric app and follow the steps to configure your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005)

164—Heat pump must be serviced service. Reach Service Experts Heating & Air Conditioning at 587-404-0790 for help.
168—Wi-Fi radio error. Call Service Experts Heating & Air Conditioning at 587-404-0790 for support.
170—Internal memory error. Call Service Experts Heating & Air Conditioning at 587-404-0790 for support.
171—Set date and time. Complete these settings so scheduling can work.
173—Thermostat temperature sensor error. Reach Service Experts Heating & Air Conditioning at 587-404-0790 for support.
175—AC power resumed. No action needed.
177—Indoor temperature sensor error. Contact Service Experts Heating & Air Conditioning at 587-404-0790 for support.
178—Outdoor temperature sensor error. Call Service Experts Heating & Air Conditioning at 587-404-0790 for support.
181/182—Get a new air filter. Clear the screen by tapping “dismiss” after putting in a new filter.
183—Wash humidifier tank and install a new water filter. Clear the display by hitting “dismiss” after finishing these procedures.
184—Get a new humidifier pad. Clear the display by touching “dismiss” after installing pad filter.
185—Get a new dehumidifier filter. Clear the display by tapping “dismiss” after putting in a new filter.
186—Wash ventilator core. Clear the display by touching “dismiss” after doing this task.
187—Wash or install a new ventilator filter. Clear the screen by tapping “dismiss” after getting a new filter.
188/189—Get a new UV bulb. Reach Service Experts Heating & Air Conditioning at 587-404-0790 for assistance.
210—Register online for outdoor temperature. Use the Lyric app to do this step and ensure proper thermostat operation.
388—Register online for remote access and exterior temperature. Download the Lyric app to finish this step and ensure correct thermostat operation.
399—No Internet. Confirm 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 up. Get the Lyric app and follow the steps to connect your thermostat.

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

Our Experts are Here to Help

If you’re still having issues after working through the troubleshooting list, our pros are available to assist you. Call us at 587-404-0790 and we’ll arrive as fast as we can to figure out the problem.

If you have an older thermostat, now is a great time to think over a replacement. Thermostat technology has advanced lately Ask us for more details on how smart thermostats can make your home better while helping save on heating and cooling expenses throughout the year.

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