A round duct damper axle bends the spiral wall and jams

A damper shaft needs solid support. Reinforce the axle area or replace the damaged fitting before relying on the damper.

Airflow, Noise, Vibration & TAB 2nd Year YELLOW

Watch out

Do not leave a damper blade stuck open or shut and call the handle position good.

Check

Check blade movement from fully open to closed.
Look for warped metal around shaft penetrations.
Verify damper is rated/appropriate for that duct and velocity.
Reinforce shaft area with approved hardware/detail.
Confirm control handle/regulator locks after repair.

Steps

Check blade movement from fully open to closed.
Look for warped metal around shaft penetrations.
Verify damper is rated/appropriate for that duct and velocity.
Reinforce shaft area with approved hardware/detail.
Confirm control handle/regulator locks after repair.

Say this to your foreman

The round damper at [location] is jamming because the shaft is warping the spiral wall. I checked blade movement. Do you want a reinforced damper fitting/backing plate installed?