Diagnosis
The Honeywell Home T6 Pro is likely locked into a "Permanent Hold" state. This occurs when a user manually adjusts the temperature on the home screen without specifying a duration for that change. In this mode, the thermostat ignores all programmed time-of-day setpoints (Wake, Away, Home, Sleep) and maintains the manually selected temperature indefinitely. You can confirm this by looking at the main display; if the words "Permanent Hold" or "Holding" appear prominently near the current temperature reading, the internal logic has suspended the schedule execution. This issue often stems from a misunderstanding of the "Hold" button logic. On the T6 Pro, a simple temperature override becomes a Permanent Hold by default unless the "Temporary Hold" setting is enabled in the Installer Setup (ISU). If the device is stuck in this state, the internal clock may be correct, and the schedule may be perfectly programmed, but the software is instructed to prioritize the manual override over the programmed logic.
How to Fix It
To release the hold and return the thermostat to its programmed schedule, follow these precise steps:
- Locate the main screen and identify the "Hold" or "Permanent Hold" text.
- Press the Menu button on the front panel to enter the system settings.
- Use the arrow keys to navigate to Schedule and press Select.
- Observe the current day's programming. If the screen indicates a hold is active, you will see a specific prompt to "Run Schedule" or "Remove Hold."
- Press the Run Schedule button (or the specific button mapped to "Remove Hold" on your specific T6 Pro firmware version).
- The display should now change from "Permanent Hold" to "Following Schedule."
- Press the Home or Back button to return to the main screen. Verify that the "Hold" text has vanished and the target temperature matches the current scheduled setpoint for that time of day.
If That Didn't Work
- Verify the System Clock and Date: If the date or time is incorrect, the thermostat may be "following the schedule," but it is following the schedule for the wrong time of day. Go to Menu > Date/Time and ensure the AM/PM indicator and the current year are correct. If the clock is off by 12 hours, the thermostat will hold the "Sleep" temperature during the day.
- Check the "Hold" Configuration in ISU: If you want the thermostat to automatically return to the schedule after a few hours rather than staying in Permanent Hold, you must change the hold type. Enter the Installer Setup (ISU) menu by holding the Menu button for several seconds. Navigate to the "Hold" setting and switch it from "Permanent" to "Temporary." This ensures that manual overrides only last until the next scheduled period.
- Audit the Programmed Setpoints: It is possible the schedule is being followed, but all time periods (Wake, Away, Home, Sleep) have been accidentally set to the same temperature. Navigate to Menu > Schedule and cycle through each period for the current day. If every period is set to 72°F, for example, it will appear as though the schedule is being ignored.
- Perform a Soft Reset: If the software is glitching and refusing to release the hold, remove the thermostat from the wall plate for 30 seconds. This power-cycles the logic board and clears temporary cache errors without erasing your programmed setpoints.
Heads Up
- Battery Warning: If you are using a T6 Pro that relies on batteries (non-C-wire installation), low batteries can occasionally cause the processor to reset to default settings or "freeze" the hold status. Replace AA batteries every 12 months to avoid erratic scheduling.
- Avoid "Rapid-Fire" Adjustments: Pressing the temperature arrows rapidly can sometimes trigger a Permanent Hold command in the firmware. Wait one second between presses to ensure the command is registered correctly.
- C-Wire Stability: If your thermostat frequently drops the schedule or resets to a hold, check the 24V C-wire connection. Intermittent power fluctuations can trigger a reboot that defaults the unit to a manual hold state for safety.