SDR ASAA2023070643905

Service difficulty report · Modulating Valve · Boeing 737890

Difficulty date: July 6, 2023
Submitted: July 7, 2023
Operation: Air carrier
Aircraft: N570AS
Make and model: Boeing 737890
Aircraft serial: 35185
Aircraft time: 59,466 hours, 17,746 cycles
System (JASC): 2150 · Cabin Cooling System
Part: Modulating Valve
Part number: 3989083
Part serial: 2578
Condition: Faulty
Location: Lh Ecs Bay
Part time: 86,462 hours, 33,726 cycles
Stage of operation: CL
How discovered: O
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

LH PACK LIGHT ON CLIMBOUT, RESET AFTER MASTER CAUTION RECALL WAS RESET. GROUNDED - YES. BITE CHECK OF #1PZTC FAULTS "TCV THIS PACK", PERFORMED FIM 21-62 TASK 830, FAULT DOES NOT RESET, NEED V139, TCV..REMOVED & REPLACED LH TEMP CONTROL VALVE. REF.AMM 21-51-10. OPS & LK CK GOOD.