The Run/Hold button controls the automatic schedule operation. In hold mode, the current temperature is
maintained until changed by manual or remote network command. In the run mode, the schedule loaded into
the thermostat is activated and setpoints will change according to the schedule and the time and day of the
Away mode. There is also an away mode that you can select if you press and hold the Run button for three
seconds. In the away mode, the setpoints are changed to preset temperatures: 66°F heating and 80°F cooling.
The Thermostat control screen has the following LED labels and descriptions, numbered from top to bottom.
LED 1 green, system operation display
LED off, SYS OFF displayed. HVAC system is off.
LED off, SYS MOT displayed. Minimum off time (MOT) delay on is active.
LED on, SYS ON displayed. HVAC system is running.
LED on, SYS MRT displayed. Minimum run time (MRT) delay off is active.
LED 2 green, system Economy mode display
LED off or on, Econ displayed. Economy or first stage heating or cooling only.
LED on, 2nd Stg displayed. Stage two heating or cooling is active.
LED on, 3rd Stg displayed. Stage three heating is active.
LED on, Vent displayed. Fresh air venting is active.
LED 3 green, Run/Hold display shows state of schedule Run/Hold mode
LED off, Run displayed. Schedule is running.
LED on, Hold displayed. Schedule is off, temperature setpoint hold in effect.
LED 4 red, alert LED used for messaging and other system alerts
LED off, No msg displayed. No text messages or alerts present.
LED on, mail icon or alert text displayed. Message waiting or specific alert text.
Communication error display
If the WDU is not properly wired or if communication to the control unit is interrupted, the LCD display will
displayed). Momentary display of communication failure caused by loss of data, will clear automatically when
data communication is restored. If the communication failure display stays on, check wiring or the control unit
at the top center of the Thermostat control screen (where outside temperature is normally