Static field route #19098

What do I do when VAV sensor tubes are pinched against structure?

Equipment Connections: RTU, AHU, VAV, Fans & Louvers⚠️ CHECK BEFORE YOU FIXV191 answer-gap expansion

📖 Verified core answer

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.

Open in Field Rescue Open category

Field verification checklist

Inspect the clear/pressure tubing from flow ring to controller.
Look for kinks, flattened spots, disconnected tubes, or reversed ports.
Check box clearance to beam/deck and hanger adjustment available.
Replace damaged tubing with a smooth route and no sharp bends.
Coordinate controls/TAB verification after correction.

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?

Text to foreman

Route options

AMake the field correction only if it is within your assignment and the approved method.

BHold and document the condition if the fix affects airflow, access, life safety, pressure class, rated assemblies, equipment, or another trade.

CBring the foreman/detailer the location, what you checked, and what decision you need before cover, startup, or rework.

Do not do this

Do not force a VAV tight to structure and crush the control tubing just to gain ceiling space.

Why this matters

Bad sensor tubing can make a good VAV box behave like a controls failure and starve or overfeed a zone.

Final verification

Use this as field training guidance. Final direction still comes from the foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements.

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