A musty or sour smell that appears when the system starts usually begins at the evaporator coil or a standing-water condensate pan, not in the ductwork. Persistent dust, filters that darken within weeks, stale air in some rooms, and uneven humidity point to duct leakage, poorly fitted filters, blocked returns, or inadequate ventilation. In tightly sealed Ohio homes running gas heat all winter, low humidity and poor air exchange are a common pairing.
A burning or hot-metal smell on the first firing of the season is normally dust burning off and clears within an hour. A smell that persists, or anything resembling gas, is different and the system should be shut off. Pro HVAC connects households in Hamden, OH with HVAC professionals who can inspect the coil, pan, filtration and ventilation. Call (321) 463-9811.
