If you have a central heating furnace, you might want to check its air filters now even though you might have done so a few months ago. With a cold winter upon us, you know that you have been demanding a lot from your furnace lately and so you want to be sure that it’s giving you all it’s got.

But if your air filters are not clear, your furnace has to work longer and harder to maintain the temperature you want. Clogged filters reduce your air flow, increase operating time and so increase your energy bill. And severely clogged filters can even lead to damage.

So check your air filters at least every three months of furnace operation; even better, check them once a month during the heavy heating season. Just shut off the electricity

to your furnace and pull out the filters. Hold them up to the light for visual inspection and you can quickly see just how filled up they might be. Replace them with new ones, which are cheap enough. Or wash them out if they are the permanent variety. Put them back in and turn on the electricity – and know that you’re saving energy while getting the full measure of air flow that your furnace is designed to deliver.

While you’re at it, check out your vent system and chimney connections for signs of leaks, corrosion or other problems. And be sure that the area around your furnace is clear of obstructions.