TinnerFlow™3rd YearVAV / TABYELLOW · Check First
Back-to-back offsets at a VAV inlet can spin and disturb the airflow before the sensor. Give the VAV a smoother approved inlet path instead of dumping turbulence into the box.
A VAV inlet sensor needs a stable air profile. Back-to-back sharp offsets, especially flex or hard 90s, can create swirl right before the box and make TAB readings bounce around.
Check the inlet condition, available straight length, obstruction, and submittal requirement. The likely recovery is a revised rigid spool, smoother offset, relocated box, or approved inlet condition so the air settles before the sensor.
Use this as training guidance. The foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements always control the final answer.