A B737-700 fueling panel crossfeed valve was left open after fueling which removed control from the ...

Narrative:

We leveled off at cruise altitude of FL390; and noticed that we had a large fuel imbalance; 5.88 pounds on the left tank; 7.08 on the right tank. Checked positions of all fuel switches and try to crossfeed. The light for the crossfeed would not illuminate but would test as operative (light only). Checked the breaker panel and found the circuit breaker for the crossfeed valve popped. [We] referred to the QRH. By turning off left tank pumps; the fuel slowly began to balance. After reviewing the weather at our destination (less than 1 SM with snow) we decided to return to the departure airport. After coordinating with ATC and company; we started a turn toward that airport. After the fuel balance got to closer tolerances we turned all main tank pumps back on. Fuel continued to burn from the right tank only. At that time I declared an emergency and requested vectors for landing an en route airport. Continued to the divert airport; notified company and landed without further incidence. We landed with 5.63 on the left tank and 4.80 on the right tank. Maintenance told us that the fuel valve on the fueling panel had been left open causing the fuel cross feed breaker to pop and fuel to be drawn unevenly.

Original NASA ASRS Text

Title: A B737-700 Fueling Panel crossfeed valve was left open after fueling which removed control from the cockpit crossfeed valve so after a fuel imbalance developed an emergency was declared and the flight diverted.

Narrative: We leveled off at cruise altitude of FL390; and noticed that we had a large fuel imbalance; 5.88 LBS on the left tank; 7.08 on the right tank. Checked positions of all fuel switches and try to crossfeed. The light for the crossfeed would not illuminate but would test as operative (light only). Checked the breaker panel and found the circuit breaker for the crossfeed valve popped. [We] referred to the QRH. By turning off left tank pumps; the fuel slowly began to balance. After reviewing the weather at our destination (less than 1 SM with snow) we decided to return to the departure airport. After coordinating with ATC and company; we started a turn toward that airport. After the fuel balance got to closer tolerances we turned all main tank pumps back on. Fuel continued to burn from the right tank only. At that time I declared an emergency and requested vectors for landing an en route airport. Continued to the divert airport; notified company and landed without further incidence. We landed with 5.63 on the left tank and 4.80 on the right tank. Maintenance told us that the fuel valve on the fueling panel had been left open causing the fuel cross feed breaker to pop and fuel to be drawn unevenly.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	997431
Time
Date	201203
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Fuel Distribution System
Person 1
Function	Pilot Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy Inflight Event / Encounter Fuel Issue

A B737-700 fueling panel crossfeed valve was left open after fueling which removed control from the cockpit crossfeed valve so after a fuel imbalance developed an emergency was declared and the flight diverted.