When my son had graduated from college, he got a great job and became a homeowner. It really upset me when I found out that he wasn’t taking care of his HVAC system. I was really upset when I walked into his house and found out that his air quality was so poor. I told him how important it was to take care of the HVAC system. I explained how necessary it was to change the air filters in the HVAC system, at least every other month. He told me that he had checked the air filter and it didn’t seem to be very dirty. He didn’t want to waste the money by changing the air filter, if it wasn’t dirty. I couldn’t believe how cavallier he was about the maintenance of his HVAC system. He knew that dirt could build up quickly, on the air filter. He used to change the air filters in the furnace and air conditioning, when he lived at home. I had often explained that when the air filter gets dirty, the HVAC system doesn’t work efficiently. A clogged air filter can even cause the HVAC to malfunction and even break down. I asked him how high his energy bills were and he tried to change the subject. I knew that I was right about this. I told him that the energy bills were indicative of how well the HVAC was working. He needed to have the HVAC maintained and cleaned. I even told him how much cheaper it would be if he were to purchase a maintenance and repair agreement with the local HVAC company. It would be much cheaper than paying for the HVAC repairs as they happen.