The very first thing to know about wifi thermostats has nothing to do with a thermostat and everything to do with a wire. The name may imply wireless connectivity, but a wifi thermostat begins with a c wire. Confused? A few minutes to educate yourself about digital thermostats can pay off by saving hundreds of dollars in energy costs.

What is a Wifi Thermostat?

A wireless thermostat—also called a digital, internet or wifi thermostat—automatically controls your heating, ventilation and air conditioning (HVAC) system while also communicating with you, wirelessly.

You can learn about your home’s interior environment (temperature, indoor air quality, humidity) remotely, from a smartphone, computer, laptop or other internet device. Monitor a vacation house from home, or home from your vacation house. Monitor field offices, commercial buildings, apartments or warehouses, all from your present location and with the touch of a screen.

What is a C Wire?

To make the most of your digital thermostat, you must have a c (common) wire capable of providing sufficient power between the wall-mounted internet thermostat and your furnace, boiler or air handler. The mini-computer of a wifi thermostat needs extra power to light the screen, run the processor, and store information. A c wire is a five-strand, 24-volt wire that you may need to buy to replace the two- or four-strand wire behind your old thermostat.

What Can a Wifi Thermostat Do?

An internet thermostat makes the old, round thermostat seem positively Paleolithic by comparison:

Schedule changes—download a smartphone app and you can remotely change your heating and cooling schedule to conserve money and energy

Reprogramming—a wifi thermostat adjusts for daylight saving and standard time shifts, gives you a menu of choices on a touch screen, and can be reprogrammed from anywhere

Peace of mind—you can check in anytime, to monitor your home

Report—a wifi unit can report out your energy usage, temperature variances, need for filter replacement, and even heating and cooling degree days

I say, do be a pal—some digital thermostats have voice control, so you can simply tell the thermostat to increase heat or make the air cooler

What Advantages Does a Wifi Thermostat Have?

In addition to the charm and high-tech of wireless connectivity, digital thermostats save you energy, lower your cooling and heating costs, and conserve resources. Imagine investing a few hundred dollars one year to annually recoup hundreds of dollars for ten to fifteen years.