The most cause of black dust blowing from your bathroom vent is built-up lint and debris in the vent ductwork.
As this debris builds up, it obstructs airflow through the ductwork and can blow back into the bathroom when the fan turns on. .
Bathroom vent ducts tend to accumulate moisture, especially if the fan ductwork has any leaks or poor connections.
To confirm the source of the dust, inspect the exhaust vent ductwork.
Start by removing the cover grille on the wall to access the exhaust fan unit.
Step Disconnect the ductwork from the exhaust fan housing to access the entire duct length...
Step Once the duct is clear of dust, reattach the ductwork securely to the exhaust fan housing with all joints and seams connected and no gaps...
or if the dust issue persists, contact professional duct cleaning service.
Jonathon Jachura is homeowner with hands-on experience with HVAC, gutters, plumbing, lawn care, pest control, and other aspects of owning home.
She has reviewed content across categories that matter to homeowners, including HVAC services, home renovations, lawn and garden care, products for the home, and insurance services.
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