Honeywell Thermostat Not Working After Battery Change (2023)

After a hard day at work, installing a Honeywell thermostat has made my house a cozier place to return to. Using the Honeywell thermostat makes my heating systems equipment function more efficiently, which results in lower utility bills.

Best of everything, I only had to replace the thermostat’s batteries once a year! However, as soon as I swapped out the battery, the thermostat ceased to function. Without contacting for expert assistance, I repaired my thermostat after much uncertainty and poring through the instructions.

I’ll take you to step by step through the process of achieving the same result. We’ll start with the most basic fixes, such as replacing the thermostat’s battery, before moving on to more involved fixes like performing a factory reset.

For Honeywell thermostat problems after a battery replacement, ensure the batteries are of the right kind and placed correctly. Reset the thermostat to its factory settings if the problem persists.

Ensure You’re Using The Correct Type of Batteries

If your Honeywell thermostat still doesn’t function after changing the batteries, you may have the incorrect batteries in there. Your thermostat’s fresh batteries may be insufficient to keep it running. To find out what boost converter your batteries need, go inside the battery compartment. For the most part, they use 1.5V AA batteries.

Replace All Batteries In One Go

If you didn’t replace all of the batteries at once, the thermostat might no longer function properly. It’s best if you keep new and old things apart. Replace your Honeywell thermostat’s batteries at least once every year with brand new ones. Your thermostat may have troubles if the old and new batteries have different charge levels.

Ensure the Batteries Are Correctly Installed

Whether the thermostat does not function, check to see if the batteries are put correctly. Make sure the batteries are put correctly by checking the battery compartment again.

If the thermostat isn’t working, make sure the batteries are installed properly before attempting any fix. Check the battery compartment. One more step is to make sure the cells are properly installed.

Factory Reset the Thermostat

Resetting your thermostat to factory settings is an excellent approach to address any issues you’re having.

Warning: If you do a Factory Reset on your thermostat, you will lose all of your data and have to start again.

I’ll walk you through the process of resetting any Honeywell thermostat to its factory default settings. Later on, I’ll go through each of the models in detail with you.

Follow these steps to reset your thermostat:

  • Turn off the thermostat if necessary.
  • Unlock the battery compartment’s door. Place a penny or other small object in the slot and then slide the compartment door to release it.
  • Now, remove the batteries from the device.
  • Replacing the batteries is as simple as reversing the polarity of the battery holders’ markings.
  • The batteries should remain in this position for about five seconds.
  • Next, remove the batteries and reinstall them according to the manufacturer’s instructions.
  • The screen may now be lit, indicating that it is operating properly once again.
How To Reset Honeywell Thermostat

How to Factory Reset Honeywell T5+, T5, and T6 

Follow these procedures to restore the factory settings on the Honeywell thermostats listed above:

  • Check to see whether your gadget is on and ready to use.
  • Hold down the Menu button for a few seconds to bring up the menu
  • Select “Reset” from the menu on the left.
  • Click “Select” to select a factory.
  • When prompted, click “Are you sure?” and then click “Yes.”
  • As a result, your device has now been completely reset.

Resetting Honeywell Smart/Lyric Round Thermostat

Follow these simple steps to reset a Honeywell Thermostats model like the Smart/Lyric:

  • Press and hold the Weather button until you see the Navigation button appear on the screen.
  • Please make your way to Factory Reset by scrolling down till you see it. Decide on it
  • Once you’ve done that, click “Ok” and “Yes.”
  • The device you’re using has now been reset.

Contact Honeywell Support

If none of the suggestions above help, you may need to seek professional guidance. To repair your thermostat, speak with a local professional or perhaps the Honeywell Support team.

It’s possible that diagnosing the problem is too unsafe without the proper equipment and expertise, therefore hiring specialists is the best option.

Fixing Your Honeywell Thermostat is Pretty Easy

I’ve shown you how to get your thermostat working again after changing the batteries. Most of them have been do-it-yourself projects. You may have to hire specialists if none of these options work out for you.

When you reset your thermostat to the manufacturer’s settings, remember to be cautious. All your settings will be wiped clean, and you’ll have to start from scratch. As a result, before doing a reset, make an effort to recall or write down your previous settings.


1. Why is my thermostat in delay mode?

To keep your HVAC system safe, turn on the delay mode. To prevent the equipment from resuming too rapidly, this delay is used. The delay mode has a maximum duration of five minutes.

2. Why Does My Honeywell thermostat say temporary?

If your Honeywell thermostat displays a “temporary” notice, it means that all of your planned temperature settings are presently on pause while you wait for the problem to be resolved.
As long as the hold period is active or overridden, the current value will also be the set temperature. The temperatures will return to normal when the hold period has ended.

3. How long does a temporary hold last on a Honeywell thermostat?

You may temporarily override a preset temperature on a Honeywell thermostat by using the temporary hold option. Useful if you need to alter your schedule for a particular length of time. There is normally an 11-hour hold-time limit.

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Lance Ulanoff is a renowned tech journalist, commentator, and on-air expert with over 36 years of experience. He has held esteemed positions including Editor in Chief of Lifewire and Mashable, where he delved into the impact of technology on daily life. Lance's expertise has been featured on major news programs globally, and he has made appearances on Fox News, CNBC, and the BBC.