Chimney-style range hood with a glass canopy over a cooktop

Generic photo: Bilguun Gantumur · Pexels License

Water dripping from the range hood (condensation in the hood or duct, cold-weather backdraft)

Warm, humid cooking air condenses on cold hood surfaces and on ductwork running through a cold attic, wall or roof. Some condensation while boiling or steaming is normal. Steady dripping usually means weak capture or airflow (dirty filters, low speed, a stuck damper, a blocked cap), an uninsulated or too-long duct, or cold outside air leaking back in when the hood is off. Water that is clearly rain coming down the duct is a roof or cap problem.

Cross-checked ~45 min moderateBrands: All

Before you start

Turn off power to the hood before removing filters or the blower housing
Use proper ladder and fall protection for roof or high wall caps; do not work on an icy roof
Do not wrap a duct with insulation that is not rated for that use near the hood's heat

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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