How to Troubleshoot Honeywell Thermostat Errors

Honeywell is one of the leading thermostat manufacturers, and we proudly install them on a regular basis in Waukegan. They’re sturdy and dependable. Plus, Honeywell is frequently updating its technology, resulting in more features for your household.

Still, every thermostat can experience problems now and then. Due to this, we’ve put together this useful manual to run through troubleshooting. While Honeywell thermostat troubleshooting problems are rare, they happen.

While you can typically solve many thermostat issues by yourself, they sometimes need Expert help. Our home comfort Experts are here to assist you when you need us. We’re just a call away at 847-306-8730.

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

What Kind of Thermostat Do I Have?

There are three models 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 reducing energy costs.
Programmable—This thermostat has a digital screen and arrows you press to choose your desired temperature. You can also choose daily programs to decrease the temperature when you’re away and increase it when you get back.
Smart—You won’t have to make any programs on this thermostat, as it learns your day. It automatically changes the temperature when you or other household members are away to help you save on utility bills. You can also change the temperature anywhere on your phone or other Wi-Fi-enabled device.

As is the case with many technologically advanced solutions, there are several malfunctions that may happen. Many of these issues don’t require Expert help and are simple to fix by yourself.

Common Honeywell Thermostat Troubleshooting Issues

Each Honeywell thermostat has a unique kind of codes matching the troubles that happen.

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

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

Display is Blank

If the screen is empty on your programmable thermostat, you might need to install new batteries. If that doesn’t take care of the problem or you rely on a smart thermostat, there could be a wiring issue.

Next, you should make sure the power is on for your furnace or air handler. Confirm the switch near the indoor equipment is switched “up”.

Also, you should confirm all furnace cabinet or air handler doors/panels are sturdily in place.

A loose panel may trigger the safety switch, which cuts off power to the system.

Less frequently, an empty screen can mean you need to get a new thermostat.

Comfort System Won’t Start

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

In the summer, confirm you set the thermostat below the ambient temperature. When it’s cool, verify it’s higher. This sounds absurd, but we’ve seen it occur lots of times.

Confirm the power switch near your indoor system is in the “on” position. You should also check the cabinet doors or panels are closed on your furnace cabinet or air handler. An open panel can trigger the safety switch, cutting off power to the system.

System still won’t start? Make sure circuit breakers haven’t tripped and that your HVAC unit isn’t showing error codes.

“Cool On” or “Heat On” is Flickering

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

Then, verify it’s signaling the right unit to start. This is often 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 setting keeps your unit from bad short cycling. This may take place if you lose electricity.

Honeywell Thermostat-Specific Error Codes

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

164—Heat pump requires service. Call Robinson Service Experts at 847-306-8730 for assistance.
168—Wi-Fi radio error. Reach Lyric technical support at 800-633-3991. 170—Internal memory error. Contact 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. Reach Lyric technical support at 800-633-3991.
175—AC power restored. No action required.
181/182—Install a new air filter. Clear the thermostat by hitting “dismiss” after installing a fresh filter.
184—Replace humidifier pad. Clear the display by touching “dismiss” after installing a fresh pad filter.
185—Install a new dehumidifier filter. Clear the screen by tapping “dismiss” after putting in a new filter.
187—Rinse or install a new ventilator filter. Clear the screen by hitting “dismiss” after installing a new filter.
188/189—Replace UV bulb. Ring Robinson Service Experts at 847-306-8730 for support.
210—Register online for outside temperature. Get the Lyric app to do this step and ensure accurate thermostat operation.
388—Register online for remote access and exterior temperature. Get 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 choose new Wi-Fi network.
508—Wi-Fi not set. Use the Lyric app and follow the steps to connect your thermostat.

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

Honeywell T6 Pro Smart Programmable Thermostat (TH411OU2005)

164—Heat pump needs service. Contact Robinson Service Experts at 847-306-8730 for assistance.
168—Wi-Fi radio error. Call Robinson Service Experts at 847-306-8730 for help.
170—Internal memory error. Call Robinson Service Experts at 847-306-8730 for help.
171—Set date and time. Finish these settings so scheduling can work.
173—Thermostat temperature sensor error. Reach Robinson Service Experts at 847-306-8730 for support.
175—AC power resumed. No action required.
177—Indoor temperature sensor error. Call Robinson Service Experts at 847-306-8730 for support.
178—Outdoor temperature sensor error. Reach Robinson Service Experts at 847-306-8730 for help.
181/182—Replace air filter. Clear the display by touching “dismiss” after adding a clean filter.
183—Wash humidifier tank and install a new water filter. Clear the thermostat by tapping “dismiss” after completing these procedures.
184—Replace humidifier pad. Clear the screen by tapping “dismiss” after getting a new pad filter.
185—Get a new dehumidifier filter. Clear the thermostat by touching “dismiss” after adding a clean filter.
186—Rinse ventilator core. Clear the monitor by hitting “dismiss” after completing this task.
187—Clean or get a new ventilator filter. Clear the display by touching “dismiss” after buying a new filter.
188/189—Get a new UV bulb. Contact Robinson Service Experts at 847-306-8730 for assistance.
210—Register online for outside temperature. Download 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 finish this step and ensure correct 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 up. Get the Lyric app and follow the procedures to connect your thermostat.

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

Our Experts are Here to Provide Assistance

If you’re still running into troubles after working through the troubleshooting steps, our Experts are ready to support you. Give us a call at 847-306-8730 and we’ll come to your house quickly to figure out the malfunction.

If you rely on an aging thermostat, now is a fantastic time to think about 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 residence more comfortable while helping save on energy bills year-round.