Date: 202202
Local time of day: 1201-1800
Location: ZZZ.ARTCC, US
Flight conditions: Mixed
Weather elements / visibility: Turbulence
Aircraft: B737-800
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Climb; Cruise
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Aircraft component: Pneumatic Duct Fire/Overheat Warning
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Human factors: Workload; Troubleshooting; Time Pressure; Distraction; Situational Awareness
Second reporter function: First Officer; Pilot Not Flying
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Weight And Balance; Inflight Event / Encounter Weather / Turbulence
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Diverted; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Landed in Emergency Condition; Flight Crew FLC complied w / Automation / Advisory
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: On Date Aircraft X flying from ZZZ to ZZZZ; on climbout about 40 minutes into the flight we leveled at FL270 but we were in bumpy weather and in and out of the clouds. We asked ATC for a climb to get above the clouds we were given Flight Level 350. We proceeded to climb to FL350 and turned on the Engine Anti Ice around 270 being in and out of the clouds and the temp was -15C (AT NO time did we ever turn on the Wing Anti Ice). Climbing through FL320 just passed ZZZ1 over the ocean we had a Master Caution/Wing Body Overheat light. I; the Captain; was the Flying Pilot and at once said MY AIRCRAFT and the First Officer got out the checklist to accomplish the Wing Body Overheat emergency/ (my aircraft and radios). The First Officer completed the checklist (did a great job); [received priority] and were going to divert to ZZZ1. After First Officer completed the checklist and the Wing Body Heat light went out we decided to return to ZZZ. ATC gave us direct to ZZZ and I transferred controls to the First Officer and I began to coordinate with ATC; and inform the Flight Attendants; the passengers and Dispatch. While flying back to ZZZ we had to land [overweight]. We chose the longest runway at ZZZ [Runway] XXC and completed the Landing Assessment on the Landing APP; and had plenty of runway to stop the overweight aircraft. Our gross weight on landing XXC ZZZ was 162 kts. and the fuel on board was 30.6k and we landed 40 Flaps 147 knots approach speed. The First Officer landed the aircraft and transferred controls at 60 knots. Exited XXC with no incident and had the Fire Chief take a look at the aircraft on the taxiway. The Fire Chief reported no issues with the aircraft and then taxied back to the gate and filled out the AML (Aircraft Maintenance Logbook) with overweight landing and Wing Body Overheat. Thanks for all the ATC controllers help and the emergency personnel. Thanks to the great professionalism of my First Officer and the calmness of our 4 Flight Attendants. Thanks to the Chief Pilot meeting us at the aircraft. Special thanks to all of the training instructors and Check Airmen who prepare us for situations such as the one we experienced.


Second narrative: Event happened on Aircraft X scheduled service from ZZZ to ZZZZ. I was assigned as the Pilot Monitoring for the flight. Preflight; taxi and takeoff were uneventful. Just before leveling off at FL350; we received a Master Caution/Air Cond/Left Wing Body Overheat light. The CA (Captain) kept control of the aircraft and I executed the appropriate QRH procedure. The light eventually went out as we worked through the steps. Due to the nature of the malfunction; we [received priority] with ZZZ2 Center and returned to ZZZ. At the Captain's request; I took over Pilot Flying responsibilities and we had an uneventful overweight landing at ZZZ on Runway XXC where we were met by ARFF (Airport Rescue and Firefighting) and escorted to our gate.I do not see any causal factors to this event. We reacted to the system malfunction and utilized our knowledge to safely return the aircraft to ZZZ.This event was a real life example of how our training can successfully play out in the aircraft. We utilized our training experience; to diagnose the issue; make decisions and keep both pilots in the green while we safely and expeditiously landed the aircraft in ZZZ.


Synopsis: B737-800 flight crew reported receiving a wing body overheat warning while in climb and cruise. The pilots; in the interest of safety; elected to make a diversion after completing the QRH procedures.