Honeywell Thermostat Battery Replacement (All Models)


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If your Honeywell thermostat isn’t turning on, it could be that the battery has died. Learn how to change the Honeywell Thermostat battery in this guide for the available Honeywell models out there.

The good news is that you don’t have to replace the entire thermostat. It’s important to note that changing the battery won’t necessarily fix the problem.

You’ll also need to check the settings on your thermostat to ensure they’re correct and that there’s nothing else wrong with the thermostat. Also, check out the How to Reset Honeywell Thermostat article, because a reset could also fix any potential software issues. 

Once you’ve done that and ruled out other issues, you can start replacing your Honeywell Thermostat battery. 

This article will cover the step-by-step instructions for Honeywell Thermostat battery replacement for all models. 

Find the Honeywell Thermostat Model Number

Before you can change the battery of any Honeywell thermostat model, you need to find out its model number. You can find it by looking at the thermostat back.

The model number will be in small letters near the bottom of the back panel, or on a small label on the front panel, or even on the digital screen itself. 

You’ll need to take the thermostat off the base plate to see the model number:

  1. Turn off the thermostat before taking it off the wall. You may need to shut off the circuit from the circuit breaker or remove the thermostat’s batteries.
  2. Carefully remove the thermostat with the connected wires. 
  3. Find the thermostat model number. 
  4. Put the Honeywell thermostat back onto the base plate and turn it on. Although, you can wait to put it back if you’re replacing the batteries. 
Where Do I Find the Model Number on My Honeywell Home Thermostat?

Honeywell Thermostat 1000 & 2000 Series

The inexpensive Honeywell 1000 and 2000 Series thermostats are great for those on a budget. These are the most popular for apartment complexes and large buildings with multiple units. 

These models have LED displays for easy control and work with your HVAC systems. 

The models that these battery replacement instructions work for are: 

  • 1000 Series Models: TH1100DV, TH1110DV, TH1210DV
  • 2000 Series Models: TH2110DV, and TH2210DV

Follow these steps to change the batteries: 

  1. Turn off the thermostat and be sure to turn the power off going to the circuit.
  2. Slowly remove the thermostat from the base plant.. 
  3. Take out the old AAA batteries and replace them with new ones. Double-check the positive and negative battery polarities match up. 
  4. Put the thermostat back on the base plate. 
  5. Turn the thermostat and circuit power back on. 
  6. All good to go with the battery change. 
Honeywell thermostat battery replacement if thermostat doesn't work AC won't turn on

Honeywell Thermostat 3000 Series

The Honeywell 3000 Series Thermostats include the TH3110D1008 and TH3210D1004 models.

They might need to have their batteries replaced once a year.  There will be an alert notification 2 months before the battery will run out of power. 

This series has a built-in compressor protection function that sets it apart from others. This feature protects your air conditioning and heating system from damage. It also has a display screen as the control system.

Follow these steps to change the Honeywell 3000 thermostat batteries: 

  1. Turn off the thermostat and be sure to turn the power off going to the circuit.
  2. Separate the cover plate from the base plate by pulling the thermostat bottom.
  3. Remove the old batteries and replace them with new batteries.
  4. Make sure the positive and negative polarities match up. 
  5. Put the cover plate back over the base plate. 
  6. Turn the thermostat and circuit power back on. 
  7. The battery replacement is now done. 

Honeywell Thermostat 4000 Series

The Honeywell Thermostat 4000 Series uses an upgraded LED display for control to set desired temperatures, control the fan, and more. 

The 4000 Series includes the TH4210D and TH4110D models. 

Follow these steps to change the Honeywell 4000 thermostat batteries: 

  1. Turn off the thermostat and turn the power off going to the circuit.
  2. Separate the cover plate from the base plate by pulling the thermostat bottom.
  3. Remove the old AA batteries and replace them with new AA batteries.
  4. Make sure the positive and negative polarities match up. 
  5. Slide the cover plate back onto the base plate. 
  6. Turn the thermostat and circuit power back on. 
  7. The battery replacement is now done. 
Honeywell PRO TH 4000 Thermostat - Service Champions

Honeywell Thermostat 5000 Series

The Honeywell Thermostat 5000 Series includes these models: TH5110D, TH5320U, TH5220D, and Focus Pro. 

The 5000 series battery compartment plates don’t need to be separated from the base plate. These thermostats also include the Auto Changeover feature that will automatically switch between cooling and heating to maintain the set temperatures. 

Follow these steps to change the Honeywell 5000 thermostat batteries: 

  1. Turn off the thermostat.
  2. Press and Pull the battery cover plate to remove it. 
  3. Remove the old AA batteries and replace them with new AA batteries.
  4. Make sure the positive and negative polarities match up. 
  5. Put the battery cover back on. 
  6. Turn the thermostat and circuit power back on. 
  7. The battery replacement is now done. 

Honeywell Thermostat 6000 Series

The Honeywell Thermostat 6000 Series thermostats have a sliding battery cover that makes it easy to change the battery. These thermostats came with some popular upgrades like the Program Schedule feature and pre-set settings.  

The Honeywell 6000 series covers these models: TH6110D, TH6220D and TH6320U.

  1. Turn off the thermostat.
  2. Press and Pull the battery cover plate from the top-right corner to remove it. 
  3. Remove the old AA batteries and replace them with new AA batteries.
  4. Make sure the positive and negative polarities match up. 
  5. Put the battery cover back on. 
  6. Turn the thermostat and circuit power back on. 
  7. The battery replacement is now done. 
How To: Replace Honeywell T6 Thermostat Batteries

Honeywell Thermostat 8000 Series

 The Honeywell Thermostat 8000 Series has Wi-Fi capabilities and a touchscreen control to set program schedules, humidity, ventilation and more from your smartphone. 

These thermostats also work with the “Honeywell My Total Connect Comfort” web portal and mobile apps to control the thermostats. 

The Honeywell 8000 models covered: TH8110U, TH8320U and TH8321U.

  1. Turn off the thermostat.
  2. Press and Pull the cover plate to remove it. 
  3. Remove the 3 old AAA batteries and replace them with new AAA batteries.
  4. Make sure the positive and negative polarities match up. 
  5. Put the battery cover back on. 
  6. Turn the thermostat and circuit power back on. 
  7. The battery replacement is now done. 

Honeywell Thermostat Lyric Round

The Honeywell Lyric Round Thermostats are a sleek and stylish thermostat with a glass display and control wheels.

They’re the first Honeywells to use geofencing technology for location-based climate control. It will locate where your phone and you are, then adjust the HVAC system to save you energy and give you comfort. 

The Honeywell Lyric also works with other smarthome devices like smart speakers and smart home hubs. 

The Honeywell Lyric Round model number is RCH9310WF. Here are the steps to change the battery: 

  1. Turn off the thermostat.
  2. Remove the thermostat from the Sub-Base.
  3. Remove the old AAA battery and replace them with new a new AAA battery.
  4. Make sure the positive and negative polarities match up. 
  5. Put the faceplate cover back on. 
  6. Turn the thermostat and circuit power back on. 
  7. The battery replacement is now done. 

Honeywell Thermostat HCW80

The Honeywell Thermostat HCW80 is a room unit that pairs with a relay module (HC60NG) to make up the Y6630D1007 set. The HCW80 grabs the room temperature and sends that information to the relay module, which then changes the temperature. 

The HCW80 uses 2 AA batteries and will last about two years before you need to change the batteries. You can also use the adjustment dial to change the temperature manually. 

Follow these steps to change the Honeywell HCW80 batteries: 

  1. Turn off the thermostat.
  2. Press and Pull the cover plate off of the base plate.  
  3. Remove the old AA batteries and replace them with new AA batteries.
  4. Make sure the positive and negative polarities match up. 
  5. Put the battery cover back on. 
  6. Turn the thermostat and circuit power back on. 
  7. The battery replacement is now done. 

Honeywell Thermostat RTH110B

The Honeywell Thermostat RTH110B model comes with a built-in thermometer to measure the room temperature and maintain your set programmed temperatures. 

Follow these steps to change the batteries on the Honeywell RTH110B model: 

  1. Turn off the thermostat.
  2. Pull the cover plate off.
  3. Remove the old batteries and replace them with new batteries.
  4. Make sure the positive and negative polarities match up. 
  5. Put the battery cover plate back on. 
  6. Turn the thermostat and circuit power back on. 
  7. The battery replacement is now done. 

Honeywell Thermostat Battery Final Thoughts

Changing the batteries on any of the Honeywell thermostat models is pretty easy. They have a simple design and they don’t require much maintenance.

You might be interested in these other articles on thermostats: 

Honeywell Thermostat Battery FAQs

What are the best batteries to use?

Most Honeywell thermostat models use alkaline or rechargeable NiMH batteries that are AA or AAA sizes. Rechargeable batteries will save you more money in the long run. There are other battery types that might be used varying on model, so you can check the Honeywell thermostat user manuals for details.

Honeywell Thermostat still won’t work after replacing batteries, what should I do?

If the Honeywell Thermostat doesn’t work after replacing it with new batteries, you can use the batteries in another electronic device to check the battery. The other thing to check is to make sure the batteries are put in correctly. If the thermostat continues not to work, you can contact Honeywell customer support

What happens when battery dies in thermostat?

When the batteries go dead, the thermostat will not function and won’t be able to adjust your home’s temperature. The thermostat will give you a “Low Battery” signal about 60 days before the battery will die. This gives you enough time to replace it with new batteries. 

What is the Honeywell thermostat battery size?

Most Honeywell thermostats use AA or AAA battery types, but not all thermostats require batteries. Some thermostats have internal batteries and will use a C-wire connection instead of batteries. Check the Honeywell thermostats manual for details on how to operate the thermostat without batteries. 

How often should I change my Honeywell thermostat batteries?

You should change the batteries every year or two depending on how much you use your thermostat. It’s recommended to change the batteries at least once a year. But Honeywell thermostats will give you a 60 day low battery warning, so you can always wait until then to change the batteries. 

How to clear “low battery” alert from display after Honeywell Thermostat battery replacement?

You can clear the “Low Battery” notification alert on the display by replacing the old batteries. The alert will disappear automatically after the Honeywell thermostat recognizes the new batteries. If the “Low Battery” doesn’t disappear, turn off the thermostat, wait 5 seconds and turn it back on.