After spending a great deal of money to purchase and install a brand new furnace, I plan to take very good care of it. I invested extra to take advantage of a higher AFUE rating, adaptable speed technology and zone control. I chose a top-of-the-line heating system and hope to keep it working at peak capacity for a very long time. I followed the advice of the HVAC contractor who installed the furnace and enrolled in a proactive maintenance plan. As part of the plan, a licensed technician will thoroughly inspect, clean and adjust the furnace every year. Having the service completed in the fall ensures that the furnace will be ready to handle the winter workload. From what I’ve read, the greatest threat to the performance of a forced air heating system is dust. Whether the furnace is running at maximum capacity or sitting idle, dust can penetrate the inner workings and settle on components. This buildup causes friction for moving parts and blocks airflow through the system. If less air is supplied from the registers, it takes the furnace much longer to achieve thermostat settings. Longer run times places added wear and tear on equipment, draws more energy and leads to higher monthly energy bill. The furnace will be more likely to malfunction and not last as long. Plus, the dust is then blown into the house, circulated throughout the various rooms and breathed by occupants. A dirty furnace degrades indoor air quality and is a threat to health and safety. There is the possibility the furnace will overheat and suffer a crack in the heat exchanger. The heat exchanger prevents combustion byproducts, such as carbon monoxide, from entering the breathing air.