Honeywell Thermostats: Changing the Batteries

Last updated on September 12th, 2020 at 07:48 pm

Honeywell is a famous brand in the thermostat industry, and it stands to reason that plenty of people use their thermostat. Honeywell actually offers several different lines and models of thermostats, and they all have their own unique features.

Some of them offer basic functions, but others are more advanced. Some models have programmable functions as well as an LED screen, and they may need batteries. If they do need batteries, eventually you’ll have to replace those batteries when they run out of power.

When Should You Change Honeywell Thermostat Batteries?

You shouldn’t wait until the batteries run out of power completely before you change them with new ones. You will get a warning about low battery power if you have a thermostat with an LED screen. The low battery warning will come on, usually saying either BATT LO or Replace Battery.

If you do see this warning, it’s best if you just change the batteries right off. If not, then your next warning is a blank screen. If you still don’t replace the batteries, eventually your thermostat stops working altogether.

Maybe you’re not all that worried about changing the batteries too quickly because your thermostat only uses the batteries for backup. However, you’ll still have problems. While most of the other programmable functions will continue working, the low battery power can cause you to lose your date and time settings. That can be rather annoying.

Replacing Honeywell 8000 Series Batteries (TH8110U, TH8320U and TH8321U)

This series offers some of the best and most advanced thermostats that Honeywell has to offer. With this, you can gain control over 2 cooling systems and 3 heating systems, plus dehumidification as well. If your thermostat is directly wired to AC power, then you may need 3 AAA batteries.

Changing the batteries involves a few simple steps:

1. Find the cover plate and take it off.
   
2. Take out the spent batteries.
   
3. Put in 3 new AAA batteries
   
4. Place the cover plate back on.

Honeywell 6000 Series Battery Replacement

These will need AA batteries instead. The steps are also quite simple when it’s time to change batteries. Follow these steps to change the honeywell thermostat battery:

1. Find the battery compartment.
   
2. Press the tab to open it. This will open from the face plate to show the batteries.
   
3. Take out the spent batteries and put in new ones.
   
4. Swing the cover back into place, and it will snap shut.

Changing Honeywell Focus PRO 5000 Battery

This category covers 3 thermostat models. Whichever model you have, you’ll find the battery compartment on the side of the thermostat.

If you have the TH5110D, you’ll need AAA alkaline batteries. If you have either the TH5320U or the TH5220D, you’ll need AA batteries.

The process here is almost the same as with the 6000 series.

1. Open the compartment by pressing the tab first.
   
2. The tab will then swing out from the face plate.
   
3. Get out the old batteries and replace them with new batteries.
   
4. Close the compartment, snapping it down.

Honeywell 4000 Series Battery Replacement

This series includes TH4210D and the TH4110D models. These thermostats are programmable models, and built to run with cooling and heating systems with or without a heat pump.

You’ll see the REPLACE BATT icon flash on the LED screen when the battery power gets low. The good news is that you’ll still have a month or two to replace the batteries before they die out completely.

Still, you may as well replace them right away so you won’t have to keep worrying about it. Follow this guide to change the honeywell 4000 thermostat battery:

1. First you need to remove the thermostat from the wall. You do this by pulling at the bottom of the face plate.
   
2. Turn the thermostat over and you’ll find the AA batteries.
   
3. Take out the spent batteries and put in 2 new AA batteries.
   
4. Place the thermostat back on the wall plate. This will snap on securely if you do it right.

Change Battery for Honeywell 2000 Series

The TH2210D and the TH2110D models are part of this series. You’ll find an LED screen, along with push- button controls. These thermostats are meant for standard heating and cooling systems and heat pumps.

Normally, a thermostat in this series will be connected to 24-VAC power. The batteries will be for backup, just in case you lose power during a blizzard. However, even if you don’t use the batteries, you should still replace them regularly. Put in new ones about once a year, perhaps just before the winter or summer season. How to change honeywell thermostat battery:

1. First switch the system off.
   
2. Take out the cover plate from the wall plate.
   
3. When you turn the cover plate over, you’ll find the 2 spent AAA batteries.
   
4. Replace them with 2 new AAA batteries.
   
5. Snap the cover plate back to the wall plate.
   
6. Switch the system back on.

Which Batteries are the Best?

You don’t really have to worry, since most AAA and AA batteries tend to work adequately. You just need to make sure you’re putting in the right type of batteries. However, if you’re insisting on putting in the best batteries, you should pick out the following brands:

Duracell

More specifically, get the Duracell Ultra Power Alkaline Battery. This is Duracell’s longest-lasting batteries, and even high-drain electronics can last for 90 hours on so on these batteries. They’re great for thermostats. By a few in reserve, as these batteries will still be good when not in use for 10 years.

Panasonic

Try the Panasonic Evolta Alkaline Battery. Plenty of people are surprised at how long these batteries last. Panasonic claims that these will outlast other batteries in its price range by 20%, and lots of users have confirmed this. This will also last 6 years in storage.

Kirkland

Get the Kirkland Signature Alkaline Battery if you’re looking for cheap batteries that offer terrific performance. They’re great for electronics that use up a lot of battery power!