Apprentice answer

Why does a VAV box act wrong when the flow sensor tubing is kinked

3rd YearVAVs, Fan Coils & Equipment ConnectionsCheck first

Pinched VAV flow tubing can make the controller read wrong or not read at all. Lower/relocate the box enough to protect the tubing and replace damaged lines.

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Plain-English answer

VAV flow pickups need clean pressure signal through small tubing. If the box is jammed into a beam/deck and the tubing is flattened, controls may think the airflow is zero, high, or unstable.

Lower or shift the box only with direction, protect the tubing path, trim/replace flattened tubing, reconnect to the correct ports, and have controls/TAB verify readings before ceiling close.

Ask Foreman

VAV [tag] has sensor tubing pinched against [beam/deck]. I checked the ports and tubing path. Do you want me to lower/shift the box and replace the kinked tubing before TAB?

Verify before acting

Use this as training guidance. Foreman direction, approved drawings, project specs, manufacturer instructions, employer safety policy, and AHJ/code requirements always control the final answer.

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