How Thermostats Work
If someone were to ask you what a thermostat does, you might look at them quizzically as if to say, why would you ask me a question with such an obvious answer? Their basic purpose is simple, of course – to keep the temperature where we want it! But answering how they work might not be as easy. So, how do they work?
Thermostats are mechanical or electronic switches. When the temperature in the room changes, these switches automatically open or close a circuit. The thermostat opens the circuit to start the burner when room temperature is below the established setting, and closes it when the right temperature is reached.
Older thermostats use a bimetallic strip, or two metals bonded together. These metals expand or contract when heat is added or taken away. When they expand and contract, a mechanical force is created that opens or closes a circuit.
A lot’s changed since the thermostat was first invented. Today many homes use programmable thermostats. These thermostats use digital sensors to read the temperature in the room. Not only are they highly accurate and responsive, they can be programmed to achieve specific temperatures on a preset schedule. They come in:
- 7-day models – Best if your schedule changes daily
- 5+2-day models – Best if you have set weekday and weekend schedules
- 5-1-1 models – Best if you have a different schedule for weekdays, Saturday and Sunday
Not only can you program your comfort around your schedule, but smart thermostats allow you to adjust the temperature from anywhere using a mobile device. In some models, the thermostat “learns” about your energy usage, the weather and other variables and adjusts for peak efficiency.