Over time, you can cut down on your home maintenance and heating costs by using washable metal air filters in your furnace. As with disposable air filters, there is a wide range of efficiency with washable metal air filters. You'll probably have to spend more for a very efficient filter. The fact that you can wash your filter instead of just throwing it away, however, can help you justify the cost of a quality filter. Instead of replacing your filter every three to four months, you may not have to buy a new one for four to five years if you clean it regularly.

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Clean a Metal Air Filter

Step 1

Use a wet/dry vacuum or the hose attachment to your upright vacuum to vacuum around the furnace.

Step 2

Remove the air filter from the furnace, and use your vacuum to remove as much dust and dirt as possible. Vacuum before you get the filter wet; otherwise, the dust and dirt will turn to mud and may be difficult to remove.

Step 3

Run water over the air filter. A kitchen sprayer works well for this; if the weather is warm, you can use a garden hose to spray out any remaining particles.

Step 4

Use a mild detergent such as dish soap to wash both sides of the filter. Rinse thoroughly.

Step 5

Use a dry cloth or paper towel to dry the filter as thoroughly as possible. Then let the filter air-dry until it is completely dry. Do not put the filter back in the furnace until it is completely dry.