That pungent smell that emits from vents when air conditioning or heating is first turned on is not merely the odor of moisture buildup and bacteria - it is also the smell of environmental pollution and money wasted. Moisture buildup on ducts and coils leads to the natural production of a sticky biological substance which can grow and become the home and breeding ground for harmful bacteria and mold. Dirt sticks to this biological substance, building up, clogging coils and blocking warm and cool air from passing through the fans. Because the coil is blocked, air tries to bypass the coil and exploit any gaps in the surrounding structures. The amount of this bypass can be significant; and since the air does not come into contact with the coil surface, it doesn't get properly heated or cooled or dehumidified. Without proper dehumidification, moisture remains in the air, flowing into rooms, thus encouraging the growth of mold that can make tenants sick (Sick Building Syndrome.) Further, since the air temperature is not being properly regulated, system fans have to work harder, costing money and wasting electricity. Traditional cleaning of ducts and coils only clears away superficial dirt, not the persistent sticky biological contamination. In short order, dirt reattaches to this substance, leading again to the blocking of fans and injection of unhealthy air into occupant spaces. At TechClean, we steam clean - versus towel clean-systems using a foaming probiotic (good bacteria) cleaner that dwells in the coil. High pressure wet steam breaks down surface contaminants in preparation for application of healthy probiotic bacteria that then populates unit surfaces, remaining active until the available microbiological food source is exhausted. Once removed, air can again pass freely through the coil, get heated or cooled more efficiently and eliminate the possibility of mold growth. Duct work is then sealed from the inside, filling in any holes or seam gaps to stop air from escaping and keep it regulated to the proper temperature. Rehabilitated—not merely "cleaned" - ducts and coils that have been restored to original condition keep the environment and tenants healthier and happier. It saves energy and money because systems don't have to work as hard, thus extending equipment life cycles. Rehabilitation can be scheduled outside of normal working hours when turning systems off causes the least disruption. To learn more, visit http://tech-clean.com/. Kenneth Coffey is the president of TechClean, Ronkonkoma, N.Y.