Reading airflow / vent-test codes

Airflow codes rate vent restriction. Clean filter, then whole duct, then hood.

Cross-checked ~45 min moderateBrands: All

Before you start

Restricted vents are fire hazards

Diagnostic steps

Unlock all 3 steps with expected values

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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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