VIBRATION TESTING REPORT - Maintenance

VIBRATION TESTING REPORT. MACHINE: Outside Air Fan. PROBLEM DISCUSSION: Bottom plot shows inboard fan bearing vibration with AHU door open. Upper plot shows inboard fan bearing vibration with AHU door closed. Elevated vibration appears to be the result of a rotating stall. The stall was produced by a closed fire damper in the discharge duct. ................
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