The good news about furnace maintenance is there are many simple things you can do that will extend the life of your heating system and keep it working optimally. For one, change the filter every one to three months (see below). You should also vacuum the blower and fan blades regularly to keep them free of dust, and inspect the vents from time to time to check for dirt and debris, and clean them as needed.You can also check the chimney annually for cracks and damage, and inspect the fan belts to make sure they’re intact. You should also hire a certified technician once a year for inspection and servicing.