New Year. New Start. Receive up to $16,000 on your New Home! VIEW ALL PROMOTIONS

It’s the time of year for air conditioners, slow-moving ceiling fans, and kiddie pools in the backyard to cool off. Your natural gas furnace is the last thing on your mind—just the thought of it makes you sweat. But the weather isn’t going to be hot forever. Soon, it’s going to be backyard-barbecue pleasant, and then light-jacket pleasant, and before long, it will be cool enough at night that you want to turn on your heater at bedtime.

The time is now to get your furnace ready for those cooler nights. Get your system checked out before HVAC technicians are in high demand, and have nice, warm air ready for that first cool night. Spire, our energy partner, offers five steps to take to get your furnace in shape.

1. Determine if it might actually be time for a new furnace.
With proper maintenance, a natural gas furnace can last up to 20 years—or even longer. If you’ve gotten two good decades out of your furnace, it could be time to respectfully retire it and bring in a replacement. With its longer lifespan and fewer maintenance needs than an electric heat pump (which will give you generally 10 to 15 years of service), a new natural gas furnace is a great choice to replace your old one. There are a lot of options available to suit your household needs, lifestyle, and budget—you can see what’s available online, and never hesitate to ask your wise, trusted HVAC technician for advice. And don’t forget to check out the rebates Spire has to offer at

2. Schedule regular seasonal maintenance.
Having a professional out once a year to examine and tune your heating system is important for getting those 20 years out of your gas furnace. That wise, trusted technician of yours will apply their expertise to the entire system—inspect all the wiring connections, vacuum the heat exchanger, lubricate the blower motor, test the igniter switch, and check out all the other parts that you don’t know the name of.

You get regular maintenance on your car, right? And your car won’t keep your bedroom cozy when nighttime temperatures suddenly drop into the 40s. Take care of your natural gas furnace, and it will take care of you.

3. Change the filter
Ideally, you’ve been changing your air filter every month. (If not, it’s never too late to start.) But it’s definitely something you want to do going into cooler weather—it improves your air quality and improves the efficiency of your furnace. If you’ve never changed it before, you’ll find your filter typically near your furnace or behind a large grate in your ceiling or wall. It’s easy to pop out the old, dusty filter and install a new one. The old filter will have its size printed on the frame, so you’ll be able to find the right size filter, at the hardware store or online, to replace it.

And now that you’ve got the filter-changing process mastered, you can do it again next month.

4. Clear out the area around the furnace.
It could be dust. It could be cobwebs. It could be hastily packed boxes of winter clothes stacked around the bottom of the furnace. (We’re not judging—we’ve all done it.) It’s best to keep the space around your furnace clean and clear to help maintain proper airflow to your furnace. 

It’s also a good idea to look around the house to see if any household items have shifted around until they’re on top of or in front of your return vents or air ducts. You want to be sure you’re getting the most out of your furnace and its wonderfully warm air.

5. Check the thermostat.
It might seem obvious, but your last step is to turn on the system briefly to make sure it works. Go to your thermostat, set the system to Heat, and crank the temperature up just a few degrees above the current temperature. The system should turn on within a couple of minutes. You might smell a mildly musty smell as your furnace comes to life after a summer off—remember when that happened last year? It’s not a big deal—but it should dissipate shortly. If your system doesn’t turn on within a few minutes, call your service provider for advice.

Then set the thermostat back to Cool, because it’s hot outside and you definitely don’t need the extra heat.

By the time cooler weather comes around, you’ll be grateful for a break from the heat—and even then, those cool evenings still might take you by surprise. Be prepared with a natural gas furnace that’s ready to go, and every fall night can be a comfy one. Thanks to Spire for helping us think ahead now and get us ready for fall.