Last summer, I had all sorts of health complaints. I dealt with frequent headaches and sore throat. I was constantly congested, sneezing and coughing. I had difficulty sleeping and very little energy in the mornings. Although I have never suffered from allergies, I thought that might be the problem. I then noticed that my health problems disappeared when I spent time outside. I realized that I usually felt much better while I was at work. My symptoms always worsened when I was at home. I became suspicious that the air conditioner was to blame. I immediately scheduled service with a professional HVAC company. The technician took the outdoor unit apart and found a significant buildup of contaminants. There was a great deal of dust and lint accumulated on the fan blades. There was algae thriving in the condensate drain. There were small bugs, debris and a great deal of mold growth. He said that whenever the cooling system operated, the pollutants were becoming airborne and spread to every room in the house. I was breathing them in and getting sick. To prevent energy waste, I’d made sure to carefully seal, caulk, weatherstrip and tighten up the house. By eliminating leaks, cracks and drafts, I’d also gotten rid of natural ventilation. The combination of the dirty air conditioner and insufficient natural ventilation led to poor indoor air quality. Along with a thorough cleaning of the air conditioner, the HVAC technician recommended the installation of a ventilator. The ventilator is designed to bring in fresh clean air and remove the stale contaminated air.