It can be severely pressing to change the air filters in your Heating plus Air Conditioning equipment. This was certainly a lesson, that I had to learn the challenging way. Two of my college buddies plus I were renting a house! Between the several of us, the house rental price was sufficient plus easily affordable. The several of us were in the senior year of our College career, plus we were only able to work part time jobs. It was pressing that our accommodations were easily affordable. We had been living in the property for about 6 months, when we observed a substantial increase in our monthly bills. The increase was much more significant than a few bucks, plus our monthly bill had risen by practically 200%. My friends plus I talked to the landlord, plus he explained that we must modify our usage habits. He also had asked us about the air filters. He asked if we had even been swapping them every month. I had never changed the air filter, plus I believe my roommates never did either. As soon as we hung up the telephone, I went outside plus looked at the Heating plus Air Conditioning equipment. I was able to find the section where the air filter was located, plus unscrewed the panel. I pulled the Heating plus Air Conditioning air filter out of the small crevice, plus it was all the way covered in black dirt. There was mold growing on the air filter. We took the old filter to the hardware shop, in order to purchase the right size plus shape. The air filter made a pretty big difference in our air quality, plus it did lower the energy bill too.