This option uses the discharge air temperature (DA-T) as the process variable for the heating and cooling loops in the air handler. When this is selected, the user can, additionally, select Reset From Outdoor Air Temperature or Alternate Reset From Outdoor Air Temperature. These two options are essentially the same, but vary slightly in how the data is defined. Reset From Outdoor Air Temperature changes the discharge air temperature setpoint as the outdoor air temperature varies. This reset schedule is defined by entering four values, the outdoor air temperature minimum and maximum values and the discharge air minimum and maximum values. When the outdoor is at the minimum value or below, the discharge air setpoint is at its maximum value. The Alternate Reset From Outdoor Air Temperature accomplishes the same function, but can be defined using the outdoor minimum and maximum values, and the discharge air setpoint and a reset span or how much to reset the discharge air while the outdoor air temperature changes.