Service difficulty report · Control Valve · Boeing 737823

Difficulty date
July 24, 2020
Submitted
August 3, 2020
Operation
Air carrier
Aircraft
N964AN
Make and model
Boeing 737823
Aircraft serial
30093
Aircraft time
57,497 hours, 23,786 cycles
Part
Control Valve
Part number
3989055
Part serial
29733
Condition
Defective
Location
Zone 100 - Fuse
Stage of operation
DE
How discovered
V
Nature of condition
J
Precautionary procedure
O

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

What was found

AIRCRAFT WAS GROUNDED: DESCENDING THRU FL 330 MASTER CAUTION AUTO FAIL LIGHTS ILLUMINATED, ACCOMPLISHED QRH PROCEDURE - MODE SELECTOR - ALTN - AUTO FAIL LIGHT EXTINGUISHED. NORMAL PRESSURIZATION. REPLACED CABIN PRESSURE CONTROLLER #2 PER AMM 21-31-01 AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK. ALSO REPLACED RIGHT HAND PACK TEMPEATURE CONTROL VALVE PER AMM 21-51-10 AS A PRECAUTION. ACCOMPLISHED A SATISFACTORY LEAK AND OPERATIONAL CHECK (NOTE: A SIMILAR ISSUE WITH THE CABIN PRESSURTIZATION THAT OCCURED ON THE SAME DAY. THE REPLACEMENT OF CABIN PRESSURE CONTROLLER #2 AND THE RIGHT HAND PACK TEMPEATURE CONTROL VALVE CORRECTED THAT ISSUE ALSO.