Honeywell T6 Pro manual

Temperature and Hold

Temporary Hold ends at the next scheduled period

1. Use + or − to set the desired temperature. With a schedule running, this creates Temporary Hold until the next period.
2. For Permanent Hold, press the Hold button, labelled at the Mode position, while the setpoint is flashing.
3. To return to the schedule, press + or − and then Cancel. This cancels either type of Hold.

The RTH2300B’s Run-button instructions do not apply to this T6 Pro. Follow the soft-key labels displayed on your screen.

Programming

Choose PROG, then the days and periods

1. Press Menu. With PROG displayed, press Select. Choose ON if you want scheduled control.
2. Select the day or group of days you want to edit.
3. Choose Wake, Away, Home or Sleep, then choose whether that period is On or Off.
4. Set the start time, heating temperature and cooling temperature, using Select to move through them.
5. Repeat for the other periods. Press Home to save and return.

The day groups and available functions depend on the installed configuration. If PROG or the expected days are absent, check the installer configuration with the installer rather than copying instructions for a different T6.

Clock and calendar

TIME and DATE are separate menu items

1. Press Menu and move to TIME. Press Select, choose 12- or 24-hour display, then set the hour and minutes. Confirm each with Select.
2. Go back to Menu and choose DATE. Use Select to confirm the year, month and day.

System operation

Mode chooses heating or cooling; Fan chooses airflow

Press Mode to cycle through the system modes available on your installation. Auto, Heat, Cool, Em Heat and Off are possible choices, but not all appear on every system.

Use Fan for blower modes. Auto and On do not mean the same thing as system Auto; Circ is another available option on supported configurations.

Display messages

Recovery and flashing Cool On describe different behavior

Adaptive Intelligent Recovery can start heating or cooling before a programmed time so the room can reach its setpoint by that time. It is not itself a fault message.

Flashing Cool On, or Heat On on a heat pump, can indicate the compressor restart delay. Allow it to finish; the troubleshooting guide says to wait five minutes for response before further checks. Do not disable protection to force a restart.

Maintenance

Use model-specific battery and filter instructions

These T6 Pro models use two AA alkaline batteries when battery power is required, or as backup on an AC-powered installation. Gently release the thermostat from its wall mount to access them, leaving the wired mount in place.

A low-battery warning is not a filter reminder. The linked pages below separate replacement from clearing a maintenance timer.

Wrong or unknown model

Match the TH number before following these controls

Check your full TH model number on your records or label. A T6 name or similar rectangular case does not establish that this user guide applies.