The owner of Absolute Comfort in Windsor says your furnace will run longer and more often with the extreme cold weather.
Bryan Hazzard says furnaces are sized more for the expected temperature, not the extreme.
He's reminding homeowners to make sure their furnace filters are clean.
"They may have run fine under normal temperatures, when it's this cold, they're running constantly.," he says. "You may run into issues."
Hazzard says with the extreme cold, he would not recommend using the scheduler for the furnace.
"Just pick a temperature you can live with and set it and forget it because it's much easier for your furnace to maintain when it's extremely cold out than having to catch up," says Hazzard.
He says it's more likely your furnace may break down with these conditions since the furnace is running longer.
"Obviously you never want it to break down but you're putting additional stress on it," he says. "So something that maybe hasn't been working great but you really didn't notice because it was milder, this is when you're going to start to find more problems and more issues."
Hazzard is also reminding homeowners to watch for ice formation on the air intakes for your furnace outside.
Windsor-Essex remains under an extreme cold warning.
Environment Canada is forecasting a daytime high of -13 degrees Celsius for the region and an evening low of -21.
With the wind chill factored in during the day, it will feel more like -25.