Static field route #15108

A diffuser, grille, or duct opening is whistling after startup. What should I check?

Airflow, Noise, Vibration & TAB Impactsyellow

Treat whistling as an airflow/noise symptom. Check sharp edges, closed dampers, tight transitions, blocked path, kinked flex, wrong diffuser, loose grille, or air being forced through too small an opening.

Open in Field Rescue Open category

Field checklist

Exact device/opening
Loose grille/diffuser face
Kinked flex or crushed liner
Damper too closed or blocked path
Sharp transition/tap location

Ask foreman

This device at [room/tag] is whistling after startup. I checked the face, flex/branch, and visible damper condition. Do you want me to hold for TAB, inspect upstream, or correct a visible restriction?

Do not

Do not bend blades, remove parts, or open/close balancing dampers randomly to silence noise.

Why it matters

Whistling usually means restriction, bad fit, excessive velocity at a device, or a missing/loose part that TAB or the foreman needs to know about.

Search words: whistling diffuser grille register noise airflow high velocity sharp edge closed damper kinked flex startup TAB whistle whistling diffuser whistling grille noisy diffuser air noise after startup high velocity restriction