Have you been using the cheapest a/c filter you can find in the Big Box store? I will confess that for a lot of years that is exactly what I did.
You will really assume what I am talking about when I described this particular A/C filter.
It’s green and it has a bunch of little swirly looking lines, and it is surrounded by cardboard that holds it all together in a rectangular shape. In case you did not think it, those particular A/C filters are almost useless. They are the definition of a waste of money. Yes you put in an A/C filter appreciate you are too, but you might as well not have bothered. These types of Heating & Air Conditioning filters are fiberglass, or sometimes called spun glass. About the only thing these do is keep big-sized debris from getting into the workings of your air conditioner. They do not help filter particles and particularly do not help supply good indoor air conditions. About the only thing that can be said for these kinds of Heating & Air Conditioning filters is that they are cheap. I recognize they are better than nothing, but just barely. The hour kind of A/C filter you are really regular with is The pleated A/C filter. I use pleated a/c filters in my proposal right now. They have more surface area and are therefore able to trap more dust and debris from the air, however once you have removed your pleated A/C filter, it can be recycled, which I truly appreciate too. UV filters are another option, then most people agree that UV Heating and Cooling filters supply good indoor air conditions. UV light kills mold and bacteria and germs, so what could be wrong with that? 
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