Health
Dust and debris can accumulate in your ducts, so that while your heating and cooling systems are pushing air through your house, they are also pushing these particles. If there is moisture anywhere in the system, the likelihood of mold developing increases, and while many molds are perfectly safe, some molds can cause serious health problems. People who suffer with allergies and asthma are particularly likely to notice the effects of poor air quality, and may benefit the most from having their HVAC (Heating, Ventilating and Air Conditioning) system cleaned.
