Indoor air often is much less healthy than outdoor air, according to Environmental Protection Agency studies. Those always closed windows and doors provide a great staging area for mold, dust, volatile organic compounds from cleaning materials, paint and printers.

However, you can dilute that stale air by briefly opening a couple windows or doors. The outside winter air will diminish the pollutants and hopefully reduce your headaches, dizziness and itchy eyes.

More help

More steps to keep your indoor air quality where you want it:

• Clean the ducts and inspect them for breaks that let your heated air vanish rather than reach your rooms.

• Make sure your heating system is clean and not spreading debris into the indoor air.

• Consider a humidifier, especially if your system provides a dry heat – bad for human skin and wooden furniture, among other things.

In New York City homes, a winter humidity level below 30 percent can lead to breathing problems, cracked skin and other issues. Most experts recommend keeping the humidity level between 30 percent and 50 percent year-round.

Need an HVAC technician? Premier HVAC staffers answer calls quickly and offer smart solutions.