SDR DALA2016092106806

Service difficulty report · Valve · Boeing 757232

Difficulty date: September 17, 2016
Submitted: September 23, 2016
Operation: Air carrier
Aircraft: N686DA
Make and model: Boeing 757232
Aircraft serial: 27589
Aircraft time: 62,995 hours, 27,403 cycles
System (JASC): 2150 · Cabin Cooling System
Part: Valve
Condition: Malfunctioned
Location: Lt A/C Pack
Stage of operation: CR
How discovered: O
Nature of condition: J
Precautionary procedure: B

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

What was found

FLIGHT 696, WHILE DESCENDING THROUGH 330, DECLARED EMERGENCY AND DESCENDED TO FL 140 DUE TO LEFT PACK FAILURE AND RIGHT PACK BEING ON MEL. TROUBLESHOT IAW FIM 21-51, TASK 803. NO FAULTS. UPON FURTHER INVESTIGATION, FOUND LEFT PACK TEMP EICAS MESSAGE. AUTO EVENT SHOWED PACK TEMP OUT TEMP -48. INSPECTED LEFT PACK. FOUND NO HOT AIR COMING FROM LOW LIMIT VALVE. REMOVED AND REPLACED LOW LIMIT VALVE B757 AMM 21-51. CHECKED GOOD.