Turning On Your Furnace: Where to Start

Updated: February 24, 2026

Your furnace has been sitting idle for several months, but now it’s frigid out and you’re ready to flip on the heat. You cross your fingers and wonder, “Will it work?”

It’s a good idea to take some simple steps before booting up your residential heater to make sure it doesn’t leave you stuck in the cold.

Here are six DIY maintenance checks to perform on your HVAC system this winter:

1. Inspect the system. Walk around your home and attic, checking for:
   • Loose connections in your ductwork
   • Signs of residue build-up on your furnace
   • Problems with your chimney vent
   • Cracks or heavy wear on your blower belt
2. Change air filters. Air filters should be changed out at least every 3 months, but it’s a good idea to put new ones in before you start up your furnace.
3. Check registers and vents. Inspect all of your air registers and return vents to make sure there is no debris or other blockage obstructing air flow.
4. Clean air ducts. Dust and debris can quickly build up in your ductwork, which can dramatically affect air flow throughout your house. Your air ducts should be cleaned regularly to avoid this and any contaminants from getting into your air. This particular task can be tricky, so don’t be afraid to call an expert for help.
5. Vacuum accessible areas. Take the hose and brush on your vacuum and use it to gently clean any areas of your furnace that are easy to access. This will help eliminate some particles and contaminants from getting into your furnace and the circulating air.
6. Consider purchasing a carbon monoxide detector. Carbon monoxide (CO) is not detectable with any of your senses, so the only way you can tell if the toxic gas is present in your home is to install a CO detector. Adding this feature will help ensure your home and family stays safe this winter.

When you turn on your furnace, don’t be surprised if there’s a burning smell for the first few minutes. This is common as your system may need to burn off some dust that’s collected over the summer, but the smell should stop pretty quickly.

If it doesn’t, it’s time to call an HVAC technician!

Taking the time to perform these small preventative measures each year can keep you from paying for costly repairs later. It’s also a good idea to have a tune-up on your HVAC system at the start of every winter so that an expert can look for any possible problems.

Further reading: What To Do If Your Home Heater Doesn’t Turn On