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Unlocking the Honeywell T4 Pro Thermostat


Have you ever accidentally locked your Honeywell T4 Pro Thermostat? Well, you’ve come to the right place! To help, we’ve put together a step-by-step video explaining the process of how you can unlock your Honeywell T4 Pro Thermostat!






1) From the locked home screen, press the center button.
2) Enter the passcode. The default passcode when the Honeywell T4 Pro is partially or fully locked is 1234. Press the Plus or Minus buttons to change the first digit of the passcode, then press the Select button. Repeat these steps until 1234 is displayed on the screen.
3) Press the Select button. The thermostat will now be unlocked. If the incorrect passcode is entered, lines will flash on the screen. Press the Back button, then follow the previous steps to enter the correct passcode.



For complete instructions and a demonstration, watch this video:

Browse our selection of thermostats, including the Honeywell T-Series at

Posted in All Posts, How Tos + Tricks, Products |

2 Responses to Unlocking the Honeywell T4 Pro Thermostat

  1. kyle says:

    How do you change the password?

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