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Replacing the batteries regularly, or as soon as the low battery indicators show up, will help keep your White Rodgers/Emerson thermostat running smoothly.

A thermostat running on low batteries can disable Wi-Fi, create automatic temperature offsets or even power down and revert to default settings.

So in this guide, I'll provide detailed instructions on how to replace the batteries in your Sensi and Emerson thermostat models.

Identify Your Thermostat’s Model

First off, you need to know your thermostat model number.

If it's not etched on the outside, you might have to check the inside of the thermostat display/cover or the inside of any button compartments.

Replace the Batteries in a White Rodgers/Emerson Thermostat

In this section, I’ll walk you through how to replace the batteries in your White Rodgers/Emerson and Sensi thermostats. 

You can scroll down and find the instructions specific to your model. I've included images of each model to make it easy to identify your one.

Sensi Smart Thermostat

1F87U-42WF

Sensi Smart Thermostat 2
  • C-Wire: Optional, but recommended for certain systems 
  • Battery Indicator: Upper right of the screen 
  • Batteries Required: 2 x AA 
  1. Firmly grab the face plate/display of the thermostat with both hands and pull it straight towards you.
  2. Locate and remove the 2 AA Alkaline batteries found on the back of the face plate.
  3. Wait until the front display of the thermostat goes blank.
  4. Then, insert 2 fresh AA Alkaline batteries into the face plate.
  5. Push the face plate back onto the wall mount. You should hear it snap or click into place.
  6. After that, wait around 1-5 minutes for the thermostat to restart and reconnect.

Sensi Lite Smart

1F76U-22WFB

Sensi Lite Smart
  • C-wire: Optional 
  • Battery Indicator: No 
  • Batteries Required: 2 x AAA
  1. Grab the face plate with both hands and pull it towards you.
  2. Take out the two AAA batteries housed in the face plate.
  3. Let the front display panel turn blank.
  4. Slide in two new AAA Alkaline batteries and firmly press the face plate back onto the wall until it clicks into place.
  5. Finally, give the thermostat between 1-5 minutes to restart and automatically re-establish its Wi-Fi connection.

Sensi Room Sensor

Additional temperature sensor that connects remotely to Sensi thermostat

Sensi Room Sensor
  • C-wire: No 
  • Battery Indicator: No 
  • Batteries Required: 2 x AAA
  1. To find the battery compartment, you must first turn the sensor over.
  2. After that, you'll find a small slot or indentation where you can easily pry it open.
  3. Once the battery compartment is open, simply take out the old AAA batteries.
  4. Now, grab your new AAA batteries and install them. Don’t forget to match the polarities (positive and negative ends) indicated inside the battery compartment.
  5. Then, close the compartment door; making sure it snaps back into place properly.
  6. Give the sensor between 1 to 5 minutes to re-establish a connection with the thermostat again.
  7. After that, confirm the connection with the sensor via the Sensi app.

Emerson Blue Series 12″ Touchscreen

1F95-1277, 1F95-1280, 1F97-1277, 1F95-1291

Blue Series 12 Emerson Touchscreen Thermostat
  • C-wire: Depends on the system 
  • Battery Indicator: Yes, the middle section of the screen 
  • Batteries Required: 2 x AA

Keep note of any “Change” messages in the middle section of your thermostat screen as this indicates that your batteries need replacing.

  1. First, pull off the thermostat from its wall mount.
  2. Then, flip over the thermostat display and you can find the battery compartment in the back.
  3. Open the compartment carefully.
  4. After that, remove the spent AA batteries from the compartment.
  5. Replace them with two new AA batteries, ensuring that you match the correct positive and negative terminals as per the engraved guide.
  6. Close the battery compartment securely.
  7. Reattach the thermostat to its base on the wall.

The thermostat will put out a small tone or beep, signaling that power has been restored.

Emerson Blue Series 6″

1F95EZ-0671, 1F95-0671, 1F95-0680

Blue Series 6 Inch
  • C-wire: Optional but recommended 
  • Battery Indicator: Yes, lower left 
  • Batteries Required: 2 x AA
  1. Start by setting your thermostat system to “OFF”. This will prevent any electrical complications or unexpected HVAC equipment operation during the battery swap.
  2. Gently remove the thermostat device from its wall mount. Be careful not to disrupt the thermostat wiring.
  3. Once the display is removed, locate the battery holder on the back of the display, usually along the top edge.
  4. Carefully take out the old batteries.
  5. Replace the old batteries with two new “AA-size” alkaline batteries. For better performance, premium brands such as Duracell or Energizer are highly recommended.
  6. After you’ve installed the batteries in the holder, reattach the thermostat to its wall mount.
  7. If your home is going to be left unoccupied for more than three months, it's best to replace the batteries with a fresh set before you depart. This ensures the thermostat won’t die out while you’re away. 
Blue Series 6 Rear View
Rear view of the Emerson Blue Series 12″ Thermostat

Emerson Blue Series 4″

1F85-0422 ,1F83-0471

Blue Series 4 Inch
  • C-wire: Optional, but recommended 
  • Battery Indicator: Yes, middle of the screen 
  • Batteries Required: 2 x AA
  1. Before you begin, make sure your system is set to OFF.
  2. To access the batteries, locate the battery door at the upper left of the thermostat’s enclosure.
  3. Then, gently lift up the battery door. This will reveal the two batteries.
  4. Take out the old batteries.
  5. Following this, insert a couple of fresh “AA” alkaline batteries. Making sure you note down the polarities. 
  6. Close the battery door by pushing it down and making sure it snaps back.
  7. Wait until the device restarts and check the battery indicator in the middle of your thermostat's screen. Make sure it doesn’t display “change.” 
Blue Series 4 Battery Compartment
Battery tab in the upper left corner of the Blue Series 4″ enclosure

Emerson Blue Series 2″

1F80-0261, 1F80-0224, 1F86EZ-0251, 1F86-0244, 1F82-0261, 1F89EZ-0251, 1F89-0211

Blue Series 2 Inch 1
  • C-wire: Optional, but recommended 
  • Battery Indicator: Yes, mid-left of the screen 
  • Batteries Required: 2 x AA 
  1. First, take out the thermostat from the wall so it’s easier to replace the batteries.
  2. Then, locate the battery door at the top left of the thermostat’s enclosure.
  3. You can then push or pull the door to loosen it and lift it open.
  4. Then, take out the old batteries.
  5. Insert the new batteries into the compartment, making sure to check the polarities indicated on the underside of the lid.
  6. Then, close the door and push everything back into place.
  7. Wait until the device restarts and confirm if the thermostat detects the new batteries. The battery indicator (at the left of the display) should indicate a full charge.

Classic 70 Series

1F75C-11NP, 1F75C-11PR, 1F75H-21NP, 1F75H-21PR, 1F75P-21NP, 1F75P-21PR

Classic 70 Series
  • C-wire: Optional, but recommended 
  • Battery Indicator: Yes, mid-left of the screen 
  • Batteries Required: 2 x AA 

Usually, the display will put out a “Change” message, indicating that it needs a fresh set of batteries.

  1. First, remove the front cover of the thermostat. You can easily pull it out from the wall mount by grabbing onto the cover and pulling it towards you.
  2. You can find the old batteries located at the top of the wall mount. Pry them out.
  3. Then, put in a fresh set of batteries, making sure to install them in the correct polarities.
  4. Finally, reinsert the front cover/faceplate back onto the thermostat.

Classic 80 Series

1F80-361, 1F82-261, 1F86-344, 1F87-361, 1F89-211

Classic 80 Series
  • C-wire: Optional, but recommended 
  • Battery Indicator: Yes, mid-left of the screen 
  • Batteries Required: 2 x AA 

In most models of this lineup, the display will put out “BATT,” “CHANGE,” or “LO” to indicate low batteries. 

  1. First, set the system switch to “Off.”
  2. Then, pull the faceplate or front cover of the thermostat off the wall mount. Make sure you pull the thin cover at the front and not the wall mount itself. 
  3. After that, you can easily locate the battery compartment at the top of the thermostat.
  4. Take out the old batteries and replace them with a fresh set
  5. Then, reinstall the cover, making sure it clicks firmly into place.

Emerson 70 Series

1F75C-11NP, 1F75C-11PR, 1F75H-21NP, 1F75H-21PR, 1F75P-21NP, 1F75P-21PR

70 Series
  • C-wire: Optional, but recommended 
  • Battery Indicator: Yes, mid-left of the screen 
  • Batteries Required: 2 x AA 

When “BATT” or “CHANGE” appears on your 70 series White Rodgers/Emerson thermostat, it's time to replace the batteries.

  1. Pull the front cover away from the thermostat baseplate
  2. You can then take out the old batteries at the top of the thermostat.
  3. After that, put in a fresh set of AA batteries, making sure the polarities are correct.
  4. After that, reinstall the front cover.

Emerson 80 Series

1F83C-11NP, 1F83C-11PR, 1F83H-21NP, 1F83H-21PR, 1F85U-22NP, 1F85U-22PR, 1F85U-42NP, 1F85U-42PR

80 Series 1
  • C-wire: Optional, but recommended 
  • Battery Indicator: Upper left 
  • Batteries Required: 2 x AA 

When the batteries need replacing, the battery icon at the upper left of the display will show an empty battery level alongside a “Replace” message. 

  1. To replace the batteries, pull the thermostat display off the wall mount. 
  2. After that, locate the battery slot at the back of the thermostat display.
  3. Then, pry out the old batteries and put in a fresh set.
  4. Reattach the thermostat display back into the wall mount

Comfort-Set® 90 Series

1F90/1F97-3XX, 1F90-60

If90 Comfort Set
  • C-wire: Optional, but recommended 
  • Battery Indicator: No 
  • Batteries Required: 3 x AA 
  1. To replace the batteries, first, pull the thermostat from its wall mount.
  2. After that, flip the device over and you’ll find the battery compartment at the back.
  3. Take out the old batteries and replace them with a fresh set.
  4. After that, reinstall the thermostat display back onto the wall. 
Comfort Set 90 Battery Replace
Location of the batteries in the 1F90 Comfort Set

IF80 Classic 80 Series

1F80-71

1F80 Classic 80 Series
  • C-wire: Recommended for most systems
  • Battery Indicator: Yes, bottom left of the display
  • Batteries Required: 3 x AA

The display will put out a “BATT” notification to let you know the batteries need replacing. 

  1. To replace the batteries, simply remove the front panel off the thermostat base
  2. You can find the batteries at the top of the thermostat base.
  3. Take out the three AAA batteries and put them in a fresh set, making sure the polarities are proper.
  4. Then, reattach the face plate, and you’re done!
If80 Comfort Set Battery Replace
Battery compartment in the 1F80 Comfort Set Thermostat

How Often Should You Change the Batteries?

Usually, the batteries on most non-smart White Rodgers thermostats can keep running for a full year. 

Meanwhile, the battery life tends to be shorter on the Sensi lineup of smart models since they utilize a constant Wi-Fi connection.

Regardless, you can extend battery life by implementing a C-wire to your thermostat. This helps resolve any lingering power issues, while also providing enough power to the thermostat so it doesn’t need to rely entirely on batteries.

Most models, even the older ones, will indicate a low battery level on the display and notify you when it’s time to replace it. 

So ideally, I recommend checking for the battery levels once a month and keeping a fresh set of alkaline batteries nearby so you can quickly swap out the old ones without running to the store. 

Wrapping Up

Fortunately, replacing the batteries on a White Rodgers/Emerson thermostat is not a very tedious process. 

You don’t need to recharge the device or use any special tools, just a set of fresh Alkaline AAAs or AAs, depending on your model. 

So make sure to check out the instructions specific to your model and drop us a comment if you run into any problems. 

Sources

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