The Daily Green Tip

With heating season around the corner, it's time to check your furnace filter. It's one of the most important parts of annual furnace maintenance.

A dirty filter will allow more dust and other contamination to circulate through your home. It also cuts down on the efficiency of your furnace, costing you more in energy expenses.

Different filters require different action at this time of year. Disposable fiberglass filters, which are the cheapest and most common filters around, should be replaced now, and regularly (usually monthly) throughout the heating season. While cheap, be aware that these filters remove as little as 10-40% of the dust, mold, allergens and other debris floating through your home's air.

Permanent filters may need to be cleaned. Electrostatic filters trap up to 88% of air contaminants, while HEPA (high efficiency particulate air) filters, meanwhile, can reduce indoor air pollution from forced-air heating systems by nearly 100%.

If you need a new furnace, buy it now. A $150 tax credit for Energy Star furnaces expires Dec. 31.

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