Winter isn’t far behind us, so you can probably remember the feeling of stepping out of your toasty-warm home into the blustery cold of a winter morning. Now that summer’s upon us, you’re likely to experience that relieved feeling of walking out of 90° heat into your comfortably air conditioned home. Both those experiences—going from cold to hot and hot to cold—are perfect examples of temperature differential.
Temperature Differential 101
When HVAC pros talk about “temperature differential,” they’re referring to the difference between the temperature inside your home and the temperature outside. Another term you’ll hear is “heat transference.” That’s the process and effect of the temperature moving from hotter to colder.
Here’s an example. Let’s say it’s a mild, winter day of 30°F outside. Indoors, your thermostat is set to a comfy 70°. That’s a temperature differential of 40°. Now you open the front door to get the morning newspaper. All that toasty heat from inside will quickly make its way outside—heat transference. Leave that door open long enough, and pretty soon you’ll feel the chilling effects indoors.
Now let’s imagine another scenario where that temperature differential is much greater. Say, -10° outside and 70° inside. The temperature differential, 80°, is twice that of the first example. Not surprisingly, the temperature transference will also double—heat will escape your home twice as fast as it did at a temperature differential of 40°. Brrrr!
Now you not only have a much colder entryway much sooner, but it will take that much more energy to replace the heat lost from your home. However, understanding that concept gives you the means to use the physics of temperature differential and heat transference to your advantage.
Using Temperature Differential to Your Advantage
Temperature differential or heat transference is what is behind the logic of setting your thermostat lower while you’re away—or setting less-used portions of your home at lower temps if you have zoned heating.
Some argue that setting back your thermostat isn’t really effective because it takes that much more energy to bring the temperature back up. But according to Keith, our resident HVAC expert at Stay Comfy, that’s a fallacy: “If you set your thermostat back from 70°F to 60°, that’s 10° less of a temperature differential, so your home will lose heat at a slower rate,” he says. And that will save you heating costs in the long run. Keith goes on to explain that the energy used to return your temperature to 70° is more than offset by the longer period of time your home is at the lower temperature. The lower you set the temperature for the longer period of time directly translates into energy—and cash—savings.
How a WiFi Thermostat Can Help
You can always manually set your thermostat lower when you leave your home and back up when you return—people have been doing that forever. However, a WiFi thermostat can help you save even more. First, you can program a smart thermostat to lower and raise your temperature automatically—no forgetting to turn down the temp as you rush off to work. Nor will you have to wait for the house to heat up when you get home—you can set your thermostat to have your home back to your ideal temperature automatically. If your plans change, you can change your thermostat’s settings from anywhere you have an Internet connection. Those are just some of the many advantages of having a WiFi thermostat. There are many on the market, but we recommend Carrier’s Cor® thermostat for its efficiency, reliability and ease-of-use.