Do not let a loose loop hanger become a cutting/crushing band on round duct.
Check
Look for strap dimples, sidewall buckles, or rub marks.
Check whether the run moves on startup.
Identify fan/damper pressure changes nearby.
Use approved rigid support/cradle where needed.
Repair or replace dented pipe if the airflow path is affected.
Steps
Look for strap dimples, sidewall buckles, or rub marks.
Check whether the run moves on startup.
Identify fan/damper pressure changes nearby.
Use approved rigid support/cradle where needed.
Repair or replace dented pipe if the airflow path is affected.
Say this to your foreman
The spiral pipe at [location] is dimpling inside the teardrop loops when the fan runs. I checked the support contact points. Do you want rigid saddles or trapeze cradles installed?