Honeywell Thermostat Troubleshooting Ultimate Guide – [All Issues Fixed]

You’re not alone if you’re having problems with your Honeywell thermostat. These devices are one of the most popular types of thermostats on the market, but that doesn’t mean they’re perfect. This post will discuss some of the most common Honeywell thermostat problems I have encountered over my 30-year career and how to troubleshoot them.

Most Common Honeywell Thermostat Problems

To avoid a service call, here are some common Honeywell thermostat problems you can troubleshoot and fix on your own.

Honeywell Thermostat Completely Unresponsive

One of the most common problems with Honeywell thermostats is that they stop working altogether. If your thermostat is entirely unresponsive, there are a few things you can try.

First, make sure that the thermostat is getting power. The thermostat should be connected to a 24-volt AC power source. The screen will not power up if the thermostat is not connected to a power source.

Next, check the batteries. If the batteries are dead, simply replace them and see if that does the trick. If the problem persists, you may need to reset the thermostat. To do this, simply turn off the power to the thermostat at the breaker box and then turn it back on. This should reset the thermostat and get it working again.

Finally, check the thermostat’s settings. The thermostat may be set to a power-saving mode that prevents the screen from turning on. If the thermostat is in power-saving mode, change the setting to allow the screen to turn on.

See my full Honeywell Thermostat not turning on guide

Honeywell Display Screen is Blank

Blank Screen on Honeywell Thermostat

There are a few possible causes for a blank display screen on your thermostat. One possibility is that the batteries are dead and need to be replaced. Another possibility is that there is a problem with the wiring. If you’re not comfortable troubleshooting wiring problems yourself, you may need to call a professional.

If you’re lucky, the problem may be as simple as dust or dirt on the screen. Try cleaning the screen with a soft, damp cloth and see if that makes a difference.

See my full Honeywell Blank Screen guide

Honeywell Thermostat Not Working After Battery Change

First, check to see if the batteries are the right size. If they are not the right size, they may not make proper contact and will need to be replaced.

Second, check to see if the batteries are inserted correctly. If they are not, they may not make proper contact and will need to be replaced.

Third, if you have recently changed the batteries, it is possible that the thermostat was not properly calibrated when the new batteries were inserted. To calibrate the thermostat, follow the instructions in the Honeywell thermostat manual.

If you have followed these steps and the thermostat is still not working, please contact Honeywell customer service for further assistance.

Honeywell Thermostat Flickering

Is your Honeywell thermostat flickering? If so, the batteries powering it may be dead. To resolve the issue, try replacing the batteries.

Some Honeywell models also have a low battery notification, which will use a tone or the words “replace bat” when it is almost time to replace the batteries.

Honeywell Thermostat Won’t Turn on Heat

Honeywell won't turn on heat

If your Honeywell thermostat doesn’t turn on the heat, there could be a few different issues going on. If the thermostat is not level, this could also be causing the problem. Make sure to level the thermostat so that it is 100% accurate.

Read my complete guide on why a Honeywell Thermostat won’t turn on heat

Honeywell Thermostat Not Cooling

If Your air Conditioner is Turned on and the thermostat is Set to “Cool,” But Your Home is Still Not Cooling, there Could Be a Problem With the AC hardware. Check for any Obvious Problems, Such as a Blown Fuse or a Tripped Breaker. If You Can’t Find any Problems, Call a Repairman.

Read my complete guide on why a Honeywell Thermostat Won’t Cool

Honeywell Thermostat Reading Doesn’t Match Actual Temperature

If you’ve ever noticed that the temperature reading on your Honeywell thermostat doesn’t match the actual indoor temperature, you’re not alone. There could be an issue with the temperature sensor, which is responsible for sending the correct information to the thermostat. Grab a thermometer and measure the actual temperature near your thermostat to troubleshoot the problem. If these temps don’t align, you may have a sensor issue. You can either replace the broken sensor or buy a new thermostat.

Honeywell Thermostat Won’t Connect to Wifi

If the no-Wi-Fi signal indicator displays in place of the Wi-Fi strength indicator on the home screen:

There are a few things that could be causing this issue. First, check to ensure your thermostat is within your home’s Wi-Fi router range. If it is, the next step is to check the router’s settings to see if the Wi-Fi network is enabled and broadcasting. If it is, and you’re still having trouble connecting, then you may need to reset your thermostat.

If the screen is blank or frozen:

If the screen is blank or frozen, you should first try to power cycle the thermostat. To do this, simply remove the thermostat from the wall and remove the batteries for about 30 seconds. Once you’ve done that, put the batteries back in and put the thermostat back on the wall. If that doesn’t work, you may need to reset the thermostat.

Other Honeywell Thermostat issues:

How Do I Reset My Honeywell Thermostat?

There isn’t a one-size-fits-all answer to this question, as the steps for resetting a Honeywell thermostat can vary depending on the model. However, some general tips for resetting a Honeywell thermostat include turning off the power to the unit at the breaker box, removing the thermostat’s cover, and pressing the reset button (usually located on the circuit board). Once the reset button has been pressed, the thermostat should be turned back on and the cover replaced.

Honeywell Thermostat Error Codes (Definitions & Solutions)

The most common error codes that require service are:

  • E1: This means a problem with the thermostat’s power supply. Check to ensure the batteries are properly installed and the power cord is plugged in.
  • E2: This indicates a problem with the thermostat’s sensors. First, try cleaning the sensors with a soft cloth. If that doesn’t work, you may need to replace the sensors.
  • E3: This code means that the thermostat is not receiving a signal from the furnace. Make sure that the furnace is turned on and that the thermostat is properly connected to it.
  • E4: This code indicates that the thermostat is not receiving a signal from the air conditioner. Ensure the air conditioner is turned on and the thermostat is properly connected to it.

If you’re still having trouble after following these steps, it’s best to call a professional in your area. Honeywell thermostats are complex devices, and only a trained professional will be able to properly diagnose and fix the problem.

How to Program a Schedule on a Honeywell Thermostat (Th6210U2001, Th6220U2000, Th6320U2008)

You’re not alone if you’re having trouble programming your Honeywell thermostat. Many people find the process confusing and frustrating. But it doesn’t have to be that way! With a little patience and perseverance, you can get your thermostat programmed in no time.

Here’s a step-by-step programming guide to schedule a Honeywell thermostat:

  • 1. Press the “Menu” Button on Your thermostat.
  • 2. Use the Arrow Keys to Navigate to the “Sched” Menu.
  • 3. Press the “Enter” Button.
  • 4. Use the Arrow Keys to Select the Day of the Week You Want to Program.
  • 5. Press the “Enter” Button.
  • 6. Use the Arrow Keys to select your schedule’s start time.
  • 7. Press the “Enter” Button.
  • 8. Use the Arrow Keys to Select the End Time for Your Schedule.
  • 9. Press the “Enter” Button.
  • 10. Use the Arrow Keys to Select the Desired Temperature.
  • 11. Press the “Enter” Button.
  • 12. Use the Arrow Keys to Select the “Save” Option.
  • 13. Press the “Enter” Button.
  • 14. Press the “Menu” Button to Exit the Menu.

And that’s it! You’ve successfully programmed a schedule into your Honeywell thermostat.

Tips for Avoiding Future Issues with Your Honeywell Thermostat

Here are some things you can do to avoid future issues with your Honeywell thermostat.

1. Read the Manual.

This may seem like an obvious one, but it’s essential. The manual will tell you everything you need to know about your thermostat, and it’s important to read it to understand how to use it properly.

2. Keep It Clean.

Dust and dirt can build up on your thermostat and cause it to malfunction. To avoid this, make sure to keep your thermostat clean.

3. Get It Serviced Regularly.

Just like any other appliance, your thermostat needs to be serviced regularly. This will help to ensure that it continues to work properly.

4. Replace the Batteries.

The batteries in your thermostat will eventually die. When this happens, replace them as soon as possible.

Key Takeaway: To avoid issues with your Honeywell thermostat, read the manual, keep it clean, don’t use it in extreme temperatures, and get it serviced regularly.

How do I know if my Honeywell thermostat is bad?

A faulty Honeywell thermostat will usually produce one or more of the following four symptoms: Incorrect temperature readings. Displaying a low battery signal. A blank display screen. Frequent clicking noises inside the device.

Contacting Customer Service for Help With Your Honeywell Thermostat

After going through this guide, you may still be wondering how to contact customer service for help.

The good news is that Honeywell has excellent customer service, and they’re always happy to help you with any problems you may be having with your thermostat.

There are a few different ways to contact them.

The number for customer service is 1-855-733-5465.

You can also email them. The support address is If you prefer to use social media, you can tweet them @Honeywell_Home.

You can also find a lot of helpful information on the Honeywell website. Just go to and click on the “Support” tab at the top of the page.

Of course, the best way to avoid having problems with your Honeywell thermostat in the first place is to read the instruction manual carefully before you start using it.

That way, you’ll know exactly how to use it and you won’t run into any problems. But if you do have a problem, don’t worry! Honeywell’s customer service team is always happy to help.

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