Every home needs the introduction of fresh outside air. Most studies indicate that the air inside our homes is more polluted than the air outside. This pollution comes from a concentration of Volatile Organic Compounds released into the air by common products used in nearly every home. Tightly sealed homes are great for energy efficiency, but could be the cause of serious IAQ problems. Equipment used to bring outside air into the home should be regularly service and maintained. Most older homes in the Central Texas area leak enough air thru cracks and windows the recirculation is not a problem.