The air filter for my HVAC system is ginormous. When I pictured an air conditioning filter, I thought it would be comparable to a dryer’s lint trap. They really do the same thing. The lint trap catches any dust or debris from getting into the dryer. If it goes in, the dryer could overheat and breakdown. The cooling filter does the same thing for the heater and AC system. The air filter is meant to catch dust, dirt and pet dander from getting into your system. Each month the air filter then is taken out and either replaced or cleaned. This ensures that no debris will go in the system and the HVAC device will not overheat. Additionally, being up on it with HVAC filter changes ensures that your indoor air conditions are very clean. My air filter just seems obnoxiously big. It is about the size of the door on my microwave. The air conditioning filter is also not a few bucks. It is actually more like $20 a month to do an air conditioning filter change. But, what else can I do? I can switch brands or style of filters. But, I can’t change the size on my cooling filter. I think it is the huge size that is costing me. I am not getting smaller air filter holes to target my air quality. I am not picking up a scented filter. I am also not picking up a greener filter. I get the basic, giant filter on the market. This giant filter just happens to cost me a ton each month.