Pellet Stove Smoke Due to Negative Air Pressure

To diagnose this cause, check for competing exhaust fans in the home, such as bathroom exhaust fans, kitchen range hoods, or clothes dryers, which may be active during startup. Verify if the smoke leakage is reduced or eliminated by briefly opening a window in the room where the stove is located, which would indicate that the stove is struggling against an airtight room's pressure differential.

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