Why Does My A/C Filter Turn Gray?

Dirt in the Filter

• When your filter turns gray, this means that it is dirty. In fact, the gray matter you find stuck onto your filter is dirt, and dirty filters have a negative impact on your air conditioner. The dirt clogs the filter, making it difficult for air to pass through, which causes your air conditioner to have to work 5 to 15 percent harder to make the room as cool as you normally keep it. Additionally, dirt particles can pass through and cause your regular air to become impure.

Finding the Filter

• Depending on the type of air conditioner you have, your filter may be located in a number of different places, but it is usually close to the inside unit. In central air conditioning, you may need to remove a grate to get to the filter. Wherever the filter is located, they all look the same: rectangular and surrounded by cardboard.

Cleaning the Filter

• When your air conditioner filter becomes too clogged with dirt to work efficiently, you can attempt to clean off the dirt and reuse your filter. Because the dirt clings together, you can easily pull it off and wipe away the excess. Keep in mind that you should wear a breathing mask to protect yourself from dirt particles that can escape into the air while you are cleaning the filter.

Replacing the Filter

• Not all filters are meant to be reused, especially when you've exhausted a filter to the point that it is weak and bends easily. When this occurs, you must replace the filter. If you look on the cardboard, you can find the measurements printed on the side. These measurements dictate the size your replacement filter must be, so write them down for when you shop for a new filter. Any local supermarket or department store will sell filters of different sizes.