Will My Honeywell Vision Pro Thermostat Work Without Batteries?

Yes it will. Power for your Honeywell Vision Pro thermostat comes from the furnace. Batteries are generally for backup incase of a power failure. Now ask yourself, if I have a power outage my furnace won’t work anyway, so why do i need a backup set of batteries.

You won’t get the correct answer unless you search for the exact version of your thermostat because Honeywell make more than one version of the Vision Pro 8000 Touchscreen. Each with different battery requirements. The model number can be found by removing the thermostat from the sub-base.

With the question of batteries required in the Vision Pro, I called Honeywell more than once on this issue. Got more than one unsatisfactory answer. My best guess has always been to tell my customers that having batteries may enable the thermostat to retain settings like programming while the power is off. Another Honeywell tech said that the stat will maintain settings for a certain time and then the stat will go to default settings.

So I just discovered that if you just don’t give up and you keep looking that answer can be found. So from the chart I’ve linked to down below (this convenient chart) that virtually all of Honeywell’s digital thermostats have “Permanent Memory Retention” except for the TL8100A1008. Why do we need batteries?

Honeywell’s Vision Pro line of thermostats require a power wire and a common wire from the furnace to power up. This power is from the 24 volt transformer in the furnace. Obviously they require other wires to start the furnace and the air conditioner, but the thermostat will power up and program with just the “R” and “C” wires connected to the furnace.

Running your thermostat without batteries is actually a good way to prevent leaky batteries from ruining the connectors in your thermostat. I just took the batteries out of my own Honeywell TH8321R1001 Vision Pro with RedLINK and it powered up as normal. RedLINK has a modem to connect to Wi-Fi.

I personally prefer the TH8321WF1001 (#ad) as it links directly to your home modem without the need for the extra Honeywell modem. It’s a less expensive way to go. Don’t remember why I bought the RedLINK, it was years ago. Interesting thing about the TH8321WF1001, it doesn’t use batteries. Check out my article.

Some people buy the TH8321WF1001 because they do their research and find out which Honeywell thermostat does not require batteries. It strictly relies on the power from the furnace to operate.

The RedLINK version registers the temperature and humidity on the touchscreen of the stat. It gets the data from a remote wireless sensor mounted somewhere outside of your home if you should decide to use one. The TH8321WF1001 uses the weather data available on the internet for your local area.

Incidentally, just in case you’ve asked yourself, will the Honeywell Wi-Fi thermostat work without Wifi? The answer is again yes. If your Wi-Fi fails you will still have heat and air conditioning it just won’t register the outdoor temperature and the humidity and you will have lost your remote access to the thermostat.

Is My Honeywell Thermostat Dual Powered or Hard Wired?

A dual powered thermostat has both batteries and 24 volt power coming from the furnace. Hard wired only thermostats have no batteries and rely strictly on the 24 volts produced by the low voltage transformer in your furnace.

Once you have found your thermostats model number by either removing the thermostat from the sub-base or looking on the original packaging you can go to this convenient chart and look up the battery requirements for your particular thermostat.

Scroll over to “Power Method” and down to your model number and now you know the specific battery requirements for your thermostat, and a lot more information if you’re interested.

To sum it all up for now, you cannot ask generic questions about thermostats. Every manufacturer of thermostats makes a multitude of models all with different battery requirements. It’s an ever developing world out there and I hope this article opened your eyes to some ways to be more knowledgeable about your Honeywell thermostat.

If you feel I’m in error in my research and experience don’t hesitate to text or email me, I want the info to be correct, not some off the wall research done just to get views and ad revenues. You’ll find all my contact info on this site.

Chad Peterson

Chad Peterson is near 40 year veteran of the HVAC industry. "I like to explain heating and air conditioning problems in a way the average home owner can understand. "

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