Turn off the HVAC system
Remove vent covers and registers
Vacuum visible dust from vents and openings
Use a brush to loosen debris inside accessible ducts
Vacuum loosened debris with a HEPA vacuum
Clean vent covers and registers with soap and water
Replace or clean the air filter
Inspect ducts for mold, pests, or damage
Seal any visible leaks with approved duct sealant
Reinstall vent covers and registers
Turn the HVAC system back on
Schedule professional duct cleaning if buildup is heavy or ducts are hard to access