You can expect a thermostat to hold closely to the setting you have chosen, but not necessarily expect that reading to be absolutely accurate. Keeping Cool M ost thermostats let you enter completely independent programs for heating and cooling. Others let you store only separate temperature settings. You must keep the same time periods for heating and cooling, or reprogram the periods at the end of the heating or cooling season. Air-conditioners are also cycled on and off two to four times an hour by the thermostat which keeps the temperature swing to about three degrees or less.
Humidity is another factor controlled by the thermostat in the conditioned space.
Sometimes it is more important to keep the humidity relatively low than it is to have the energy savings from higher temperature settings. Programming Ease E lectromechanical thermostats are the easiest to program. Under the cover of each is a clock-timer that holds moveable tabs similar to those on a household timer. The tabs are positioned to control the setback and comfort periods. As the clock-timer dial turns, the tabs trip a switch to change the setpoint.