A round elbow heel seam blows open under high airflow
A light adjustable elbow may not belong on a high-velocity or pressure-critical run. Replace failed fittings with the approved round elbow type/radius/gauge for that system.
Do not smear mastic over a mechanically failed elbow seam and call it fixed.
Check
Shut down or isolate the section if the elbow seam is opening under pressure.
Check whether the elbow type is approved for that system and location.
Inspect for seam separation, loose screws, torn metal, or missing mechanical engagement.
Measure space for the correct replacement fitting or revised offset.
Retest after replacement and sealing per spec.
Steps
Shut down or isolate the section if the elbow seam is opening under pressure.
Check whether the elbow type is approved for that system and location.
Inspect for seam separation, loose screws, torn metal, or missing mechanical engagement.
Measure space for the correct replacement fitting or revised offset.
Retest after replacement and sealing per spec.
Say this to your foreman
The round elbow at [location] split at the heel seam under startup pressure. I checked the fitting type and system. Do you want it replaced with the approved heavier/smoother elbow detail?