I had been so busy the whole day I barely had time to look at my phone. When I looked at my phone at around eight in the evening, I found several missed calls from my son, Evans. I immediately called him back. He told me that he thought our HVAC system malfunctioned because the house was freezing. It hit me that I must have missed the alarm to readjust the temperature settings. I usually changed the settings when nobody was at home to save energy. Evans had even called the local air conditioning company asking for an a/c worker to find out what was wrong with the air conditioner. I told him there was no need for a/c repair and explained what was happening with the air conditioner installation. It was about time I taught him basic things, such as how to reset the regulator. I was no a/c representative, but I knew a few things about improving indoor air quality. I realized that he was already twelve and did not know much about the HVAC, and since it was just him and me in our house, it was paramount that he learned basic things. Other things, such as a/c service, could be left for the air conditioning supplier. As for a/c care, we would play our part in it because not everything about the HVAC system was up to the air conditioning business. I also made sure to confirm our scheduled air conditioning maintenance. I would hate to buy a new air conditioning system simply because I failed to follow up on our annual a/c care plan.