to set or adjust the time held by hvac controller 10 upon initial installation and setup of hvac controller 10 it may be necessary to enter or update the time setting in some embodiments it may be necessary to change the time setting to accommodate entering or departing daylight savings time dst in other embodiments hvac controller 10 can automatically adapt to daylight savings time in some embodiments hvac controller 10 can be in radio communication with a standard time reference source if desired touch screen 22 can display the present time at time icon 116 as illustrated the time is displayed using a 12 hour clock with an am or pm notation in some embodiments the time can be displayed using a 24 hour military clock if desired touch screen 22 also includes a screen icon 104 that can be used to temporarily disable touch screen 22 from accepting any user inputs so that the surface of touch screen 22 can be wiped off or otherwise cleaned more icon 106 permits a user to access additional features of hvac controller 10 such as scheduling reminders for filter replacement setting operational parameters for a uv lamp and the like in some embodiments touch screen 22 can include an outdoor icon 118 that displays the outside ambient temperature fig9 illustrates a step by step process for modifying a number of parameters 38 see fig1 in accordance with an illustrative embodiment of the present invention prior to beginning an editing process the thermostat.