Although my central air conditioner is only three years old, I had some problems with indoor temperature and air quality last summer. The outside temperature was only in the mid seventies, the air conditioner still had trouble keeping up. Certain rooms in the house felt overheated and sticky, while others were downright cold. The conditioned air coming from the vents had a musty odor and introduced quite a bit of dust into the home. I noticed that the air conditioner never seemed to shut off, and every time it ran, my family complained of headaches, sore throat and frequent sneezing. Since I’d been diligent about scheduling professional maintenance for the air conditioner, I couldn’t imagine what was causing all of these problems. I finally called my regular HVAC contractor to come take a look at the cooling system. He told me that there was nothing wrong with the central air conditioner, but that my ductwork was in terrible condition. There were small holes in the duct system, which was allowing the conditioned air to escape and drawing in polluted, outside air. This caused the air conditioner to run longer and work much harder to reach thermostat settings. Plus, it was introducing a whole bunch of contaminants, including pollen, dust and exhaust fumes, into the breathing air. Fortunately, the problems were resolved with duct sealing. The HVAC contractor used a process called Aeroseal, which sends pressurized air and adhesive particles into the ductwork. As the particles escape through leaks, they build up along the edges until an effective seal is formed. The process was completed in under two hours and there was no mess or damage to my home.