Service difficulty report · Regulator Valve · Doug MD88

Difficulty date
January 19, 2015
Submitted
January 26, 2015
Operation
Air carrier
Aircraft
N404NV
Make and model
Doug MD88
Aircraft serial
49765
Aircraft time
63,517 hours, 41,428 cycles
Part
Regulator Valve
Condition
Malfunctioned
Location
Ac Bay
Stage of operation
CL
How discovered
O
Nature of condition
O
Precautionary procedure
A

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

What was found

DURING CRUISE AT 25000 WITH 1 PACK OFF DUE TO MEL, WE KEPT GETTING THE FLOW LIGHT & CABIN PRESS WAS SLOWLY CLIMBING. RAN EQRH 21.8 - INCLUDING INCREASE THROTTLES PSI ON LT PACK, OPERATING PACK WAS AROUND 30PSI. WE DESCENDED TO FL220 & WERE STILL SHOWING THE FLOW LIGHT. DECISION TO DIVERT & AFTER ABOUT 5-10 MINS AT FL220 THE FLOW LIGHT EXTINGUISHED & CABIN PRESS STARTED TO COME DOWN TO THE CORRECT CABIN ALTITUDE. R & R PRESS REGULATOR VLV LT IAW MM 21-31-01 & LT FLOW CONTROL VLV IAW MM 21-31-02. OPERATIONS & LEAK CHECKED NORMAL. COMPLIED WITH SINGLE PACK OPERATIONAL TEST IAW TASK CARD F0612102. OPERATIONS CHECKED NORMAL, NO OTHER DEFECTS NOTED. RT SUPPLY TEMP HI, FOUND WIRE CHAFED FOR AIR CONDITIONING TEMP HI SWITCH B3-16 IAW SWPM 20-10-01.

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