Service difficulty report · A/C Pack · Boeing 737824

Difficulty date
May 15, 2026
Submitted
May 20, 2026
Operation
Air carrier
Aircraft
N73278
Make and model
Boeing 737824
Aircraft serial
31596
Aircraft time
65,834 hours, 23,995 cycles
Part
A/C Pack
Condition
Faulted
Location
Right
Stage of operation
IN
How discovered
V
Nature of condition
O
Precautionary procedure
K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

RIGHT PACK HAVING START UP ISSUES REQUESTING MEL 2101B FOR RH PACK IAW MEL 2102B. WILL COMPLY WITH MEL CONDITIONS UPON APPROVAL. DISPATCH DESK.OK TO APPLY MEL 2101B FOR RIGHT PACK INOP COMPLIED WITH MEL REVERSED MEL FOR TROUBLESHOOTING. BITE TEST OF BOTH BOXES SHOWED NO FAULTS. COULD NOT GET PACK TO START. DISCRETES SHOWED SWITCH POSITION CHANGE NORMALLY BUT PACK NEVER CAME ON, DUCT PRESSURE INCREASED TO 50PSI WHEN SWITCH WAS COMMANDED. DUE TO ACM REQUIRING REMOVAL COULD NOT REPLACE FLOW CONTROL VALVE WITH REMAINING GROUND TIME. ALSO COULD NOT VERIFY PACK OPERATION STATUS AT THIS TIME. RESTORED AIRCRAFT TO MEL CONFIGURATION PREFORMED PACK TEMPERATURE CONTROL - BITE PROCEDURE REF FIM 21-62 TASK 801. FOUND NO FAULTS. REACTIVATED RIGHT PACK FOR TROUBLESHOOTING PURPOSES AND OPS CHECKED IT FOUND THAT RIGHT PACK DOES NOT TURN ON RIGHT AWAY, OTHER INSTANCES IT DOES NOT TURN ON AT ALL. SUSPECT THE FLOW CONTROL VALVE INTERMITTENTLY FAULTING. IN THE INSTANCE WHEN THE RIGHT PACK WORKED NO ODOR WAS NOTICED IN THE CABIN. NOT ENOUGH GROUND TIME TO CHANGE THE PART. REF AMM TASK 21-51-01-000-805-002 FOR REPLACEMENT PROCEDURE. REAPPLIED MEL CONFIGURATIONS TO THE RIGHT PACK.