How To Reset Honeywell Thermostat Rth221B1039. The new passcode would be 2654. Make sure the honeywell thermostat is switched on.

The following steps given below show how to reset a honeywell thermostat rth9580wf. Press and hold the program button. Press the “back” arrow, then scroll down to “installer options”.
When The Number Panel Is Displayed, Set The Number On The Left To 0710 And The Number On The Right To One.
You will need to tighten the calibration screw. Use a screwdriver that fits the calibration screw. Scroll down to “thermostat information.
Install The Honeywell Rth221B Thermostat.
The new passcode would be 2654. Use a pencil to mark the hole positions, then drill holes at the marked positions and put in the wall. Scroll down until the preferences button is shown and tap on it.
Enter The Date Code When Prompted To “Enter Your Password”.
Press and hold down the menu button for 5 seconds. Bring a thermometer into the room where your thermostat is (make sure the thermometer is accurate). Make sure you have a pencil, pen, or other fine, pointed object.
Confirm Your Thermostat Is On.
Then check the settings below and change if needed: While holding the program selection, use a slender object such as a paper clip to press the reset button. Select one of the reset option and click on select.
Place It Near The Thermostat And Let The Reading Stabilize.
The button should lead to left scrolling. Now, you need to make the thermostat’s. Add 1234 to the date code.