CHICAGO (CBS) — As the temperatures continue to plummet, you may think you’re taking the right steps to keep your home warm, but experts say common heating practices may do more harm than good.

Jeremy Ashby, general manager at Temperature Pro, does furnace troubleshooting. He expects to be doing a lot of it over the next three days.

Ashby says the first thing to expect as temperatures dive into extreme negative territory is a chilly home even at a thermostats regular setting.

“Because the outside air is penetrating through the walls of your house,” he said. “So if you’ve got a brand-spanking new house that is … energy efficient then you might achieve what you’re looking for.”

Ashby says resist the urge to crank the thermostat up.

“Do not do that. You will cause the unit to run in excess,” he said. “You can cause bigger failures. You can cause major problems to the units. I highly do not recommend you jack your thermostats way up.”

Experts say the safest heating bet is set the thermostat and keep it there.

“So these colder days like negative 11 degrees, that furnace may run for an extra hour or two to try to maintain the temperature you’re looking for it to maintain, but it’s not designed to run 24 hours nonstop. No furnace is,” he said.

And radiators and boilers can have their own set of problems.

It is also a good time to change your furnace filter if it is looking dirty.