My son came to us at the beginning of the school year to tell us that he had chosen to enter an alternative program for his senior year. At first, we were concerned because he had never really liked school. He said the the program would allow him to experience a more hands on approach to his education. The main thing he was looking forward to was applying to internships that could help him decided on a career path. His teacher had an acquaintance from his basketball league who owned an HVAC company. Our son ended up working with them for the bulk of the year. About halfway through the year, he said that he thought he had seen it all when it came to HVAC maintenance, but he was wrong. Most problems could have been avoided with regular care for their air filter systems. He even found that many homeowners never even gave a thought to the fact that the ductwork needed to be cleaned either. Almost everyone thinks they are immune to any HVAC problems, until they need to call in a specialist for emergency help. The worst one he saw was an old run down apartment building. They called in for an appointment but because of the size of the job, it took about a week to schedule that many technicians. When the team walked into the building, they knew it was not going to be a fun task. The entire HVAC system had not even been touched in years. They had to completely strip the old, leaky ductwork from the building and install new ones. It was completely infested with any and every bug you can imagine. The air filters were not any better when and they needed to be changed out too.