Honeywell Heating & Cooling - Recent Questions, Troubleshooting & Support

You need to remove the thermostat from the wall plate to change the battery. Look on the bottom of the thermostat for a locking screw. Loosen this screw with an appropriate screw driver. Then pull the bottom of the thermostat away from the wall plate and then lift up from the bottom. When you put the thermostat back on, line up the brackets at the top of the thermostat with the slots on the wall plate. Then push the thermostat against the wall plate and tighten the locking screw.

The documentation for the Honeywell RTH2300B1012/U is available on the product page: . Click on the Manuals tab. See page 4 (page 6 of the PDF) for removing the thermostat from the wall plate. See page 9 (11 of the PDF) for replacing the batteries and putting the thermostat back on the wall plate. The current link to the manual is .

I hope this helps.

Cindy Wells

Honeywell... | Answered 2 days ago

On a Honeywell thermostat the flashing means that the system is in a delay to turn on the compressor. This is used to protect the compressor from coming on and off too often. The normal delay is about 5 minutes. After that the system should come on. If not there is s problem.

In order to help us help you we will need a little more information. What happens either at the inside unit or at the outside unit after the thermostat stops flashing "Cool"? Any fans come on? Do you hear a "KLUNK"? Any sparks? Please let us know so we can help.

Honeywell... | Answered on Aug 22, 2019

On the Pro4000 model you hold the 2 arrows until you go into setup mode. Then arrow up ONLY til you get to option 13. The display will read 13 and 1, press the DOWN arrow and it will read 13 and 0. This turns off Adaptive Intelligent recovery. Now hold the 2 arrows til you see the normal display screen. You are done.

I just did this with a Honeywell tech rep on the phone.

Honeywell... | Answered on Aug 16, 2019

Can be Low Battery Warning or Air Filter Reminder.


Honeywell... | Answered on Aug 15, 2019

Expose the wires and carefully put the yellow wire in with the red. See if outdoor unit kicks on.

Honeywell... | Answered on Jul 28, 2019

try this web site for your manual. I think this is what you are looking for.

Honeywell... | Answered on Jul 14, 2019

I have not seen this issue and the manual gives you the option of either off or dim to high upon key depress.
0280 Backlight 0 Backlight on for approx. 8 seconds after keypress 1 Backlight always on low intensity, full bright after keypress (requires 24VAC connection).
I am sorry I can not offer any further info.

Honeywell... | Answered on Jul 14, 2019

Without seeing the wiring diagram, I can only say that the MV/PV terminal in many cases is used as the common from the thermostat/transformer. Usually, the 24 volts is supplied to the thermostat from a step down transformer and the thermostat sends voltage to the controller. I would hesitate to "guess" at this without a complete understanding of the wiring requirements. Any HVAC tech should be able to help you.

Honeywell... | Answered on Jul 14, 2019

It has been my experience that the screen is damaged. You will most likely have to replace the thermostat. I have seen where heavy scratches will cause this condition.

Honeywell... | Answered on Jul 14, 2019

So if the temp changes what are you wanting to change? I'm confused.

Honeywell... | Answered on Jul 10, 2019

it gets its power from the unit via the data cable. go on the seely international website or the braemar website and they can put you in contact with another dealer in your area. get it fixed while still in warrenty.

Honeywell... | Answered on Jul 09, 2019

Hello, the snowflake flashing is a (supposed to be) 5 minute delay to prevent short cycling of the compressor. This delay can sometimes get stuck thus requiring replacement. To test , remove top of thermostat to where you can identify wires and terminals. Have someone stand near the ac unit for this test, and then take a wire or paperclip and briefly touch Rc to Y. This should start the outdoor unit. R to G will start the indoor fan

Honeywell... | Answered on Jul 06, 2019

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