Most programmable thermostats will control these systems. Device modules include thermostats, audible alarms and controllers for low voltage switches. Mercury switches were once common in bimetal thermostats. Some programmable thermostats are available to control line-voltage systems. Applications for hermetic sealing include semiconductor electronics, thermostats, optical devices, MEMS, and switches. Programmable thermostats are also known as setback thermostats or clock thermostats. Inside newer buildings, digital and analog thermostats display temperature settings in degrees Celsius or Fahrenheit. Timers, powered thermostats, and the like are other examples. Examples of devices with hysteresis are single-mode thermostats and smoke alarms. Most electronic thermostats use either thermistor devices or integrated logic elements for the anticipation function. This study reveals that programmable thermostats will not necessarily save energy. This effectively eliminated the issues regarding human error with programmable thermostats. Electromechanical thermostats use resistance elements as anticipators. The hotel originally had 300 rooms, each outfitted with air conditioning with individual thermostats. Electronic thermostats have an electronic equivalent.