SDR ASAA2018090425978

Service difficulty report · Ecs · Boeing 737990ER

Difficulty date: September 2, 2018
Submitted: September 4, 2018
Operation: Air carrier
Aircraft: N469AS
Make and model: Boeing 737990ER
Aircraft serial: 41702
Aircraft time: 16,309 hours, 5,438 cycles
System (JASC): 2150 · Cabin Cooling System
Part: Ecs
Condition: Malfunctioned
Location: Ac Bay
Stage of operation: CR
How discovered: O
Nature of condition: O
Precautionary procedure: O

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

What was found

AIR CONDITIONING BALANCED MODE NOT WORKING CORRECTLY LEFT PACK OUTLET TEMP IS VARIES 6* FROM RIGHT PACK OUTLET TEMP IN CRUISE RIGHT PACK OUTLET TEMP IS 20*, LEFT VARIES FROM 14* TO 20*. REFERENCE SYS HANDBOOK 2.20 PAGE 2. TRIM AIR IS ABLE TO COMPENSATE HOWEVER AND COCKPIT TEMP IS COMFORTABLE CONTROLLABLE AND PRESSURIZATION IS NORMAL. GROUNDED - YES. RESET SYS PERFORMED BIT TEST PER FIM 21-62 TASK 801, NO FAULTS FOUND, NO HISTORY.