System Airflow Investigation
Use when TAB says a system is short, a diffuser has no air, rooms are imbalanced, or startup symptoms point back to the install.
Field checklistMobile-firstCopy-ready ask
Use when
TAB/startup finds low CFM, zero airflow, whistling, vibration, high/low rooms, closed dampers, or suspected install restrictions.
First move
Start at the symptom and trace the air path backward instead of guessing.
Walk it in this order
- Name the symptom: zero air, low CFM, too much air, noise, vibration, short system, or closed damper.
- Confirm the room/device tag and what system serves it.
- Trace from diffuser/boot back to flex, branch, damper, VAV/main, and equipment.
- Check for restrictions: kinks, crushed duct, bad tap location, wrong fitting orientation, closed damper, leakage, wrong size, blocked return path.
- Separate simple install fixes from red-zone items like fire/smoke dampers or controls.
- Document findings as a clean punch list before asking for retest or escalation.
Do not
- Do not blame the unit or design before checking the installed path.
- Do not reset unknown fire/smoke/control dampers.
- Do not wander randomly; trace the system in order.
Photos / notes to collect
- Device/tag
- Damper position/access
- Flex/branch restriction
- Leakage point
- Drawing mark-up
- System punch list
Ask it clean
TAB is seeing [symptom] at [system/room]. Do you want me to walk the air path and bring back a punch list before we escalate it?