Narrative:

During preflight; after approximately 5 minutes of run time; the APU shut down. Ground power was put back on the aircraft. Then the fire bell came on with a lighted APU fire handle. Performed the APU fire actions; the light went out. I started an evacuation with the passengers exiting door 1L. The first officer called operations to get the fire trucks rolling. All passengers and crew exited the aircraft without any issues.

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Original NASA ASRS Text

Title: B737NG flight crew reported shutting down the APU at the gate during preflight when they received an APU fire warning.

Narrative: During preflight; after approximately 5 minutes of run time; the APU shut down. Ground power was put back on the aircraft. Then the fire bell came on with a lighted APU fire handle. Performed the APU fire actions; the light went out. I started an evacuation with the passengers exiting door 1L. The FO called Operations to get the fire trucks rolling. All passengers and crew exited the aircraft without any issues.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.