A person’s furnace air filter is contrived to withdraw dust from air as it passes across your furnace. The longer your furnace filter is installed the dingier it becomes. This accumulated loading of the filter with debris causes a resistance to flow of air through the filtrate and cuts back air flow.
You may be surprised to learn that the air you breathe while inside your home may be several times worse than the air outside. This is largely because of dust and other contaminants in the air you breathe indoors. Fortunately, you can use a furnace filter to help rid your home of these contaminants so you can begin breathing much cleaner air in your home.
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