All About Thermostats

A thermostat is a device that allows you to control the temperature inside of your home by controlling how your heating or cooling system functions. Heating devices are turned on when temperatures fall below a certain temperature and are turned off when the temperatures rise above another temperature. These two temperatures are separated so that the device is not being turned on or off too rapidly and are usually set within a couple of degrees from the desired temperature (or set point). More advanced thermostats can also control cooling devices so that a room can cool down faster and the air conditioner can be turned off when the air reaches the desired temperature.

There are three main categories of thermostats:

1. Mechanical Non-programmable: Inside of this kind of thermostat is a coil made of two different metal strips that are sandwiched together. This coil tips a small mercury-filled glass bottle. When the temperature inside of the room/home changes, the two metals expand differently and the coil winds or unwinds, tipping the glass bottle and rolling the mercury to one end of the bottle. The winding and unwinding of the coil controls the furnace. Usually, the temperature of the room/home stays at the point where the bottle of mercury is almost perfectly level. These are the oldest kind of thermostats but are still widely used because of their simplicity and cost effectiveness. The main drawback of these kinds of thermostats is that they are less accurate that digital thermostats and cannot support programming features.

2. Digital Non-programmable: These thermostats work similarly to mechanical non-programmable except that the metal coil is replaced with an electric temperature sensor. The microprocessor inside of it compares its readings to the desired temperature you select. Start and stop commands are then given to the heating or cooling system to bring the temperature to a level that is comfortable. These thermostats are more accurate than mechanical non-programmable but the changes in temperature settings still have to be done manually. They also do not contain mercury so they are more environmentally friendly.

3. Digital Programmable: These thermostats work similarly to digital non-programmable models but they are far more convenient. You program the thermostat to customize your heating system’s operation to fit your lifestyle and schedule, then relax and let the thermostat do the work. Simply program the temperatures you need and what times of the day you need them into the thermostat’s memory. You’ll only need to program once, until changed to your routine, lifestyle or the seasons happen.

There are four ways to program thermostats:

1. 1-Day Programming: The desired temperature can be set to change throughout the day.
2. 5-2 Days Programming: There are separate programs for weekdays and weekends.
3. 5-1-1 Days Programming: There are separate programs for the weekdays, Saturday and Sunday.
4.
7 Days Programming: There are separate programs for each day of the week.

Thermostats can be placed in convenient places and only turn your furnace on when it is needed to maintain your desired temperature. They should be located where people spend the most amount of time, about five feet off of the ground and at least 18 inches away from an outside wall. Always remember to keep your thermostat ways from any sources of heat other than the air in the room. They should be kept away from heater, vents, windows, hot-water pipes and out of direct sunlight. They work best when installed away from stairways and corners because these areas can affect the circulation of air. n