I never gave much thought to the duct system installed in my home until recently. This branching network of pipes is concealed inside walls, ceilings, and the as crawl spaces, it had been relatively easy to ignore. While I’ve been consistent about its maintenance and air filter changes for the furnace, I had never bothered with professional maintenance for the air ducts themselves. I operate the furnace for approximately 6-8 months out of the year. I then rely on the a/c for the remaining 4-5 months. If either the air conditioner or the furnace are running, the ductwork impacts comfort, air quality, safety, and energy efficiency. The cooled and the heated air pass through these pipes numerous times per day. If contaminants are present within these ducts, such as mold, dust, pollen or bacteria, it can be transferred and spread throughout each rooms in the home. This causes awful odors, dusty surfaces, as well as a myriad of health concerns. Even small holes within the duct system can allow for heated or cooled air to escape, they could also bring in outside air. If a diminished portion of the conditioned air is reaching the interior rooms, both the furnace and the cooling system will need to work a lot harder to maintain an ideal temperature. This will then lead to unnecessary wear as well and tear on its components, greater energy usage, higher utility bills, and can even affect home environment. Plus, the living space simply won’t be as comfortable. I finally hired a licensed heating, ventilation, and a/c specialist to inspect the duct system soon after my home began to host the scent of a dead mouse. I realized the smell was emanating from the ducts and then intensifying each time the gas furnace was turned on.