As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING A SCHEDULED PRODUCT IMPROVEMENT (REPLACED DUCT ASSY 6914070-67) NOTICED THE LT HEAT EXCHANGER SIDE PLATE HAD A .35 INCH LONG CRACK AND THE OPPOSITE SIDE WAS CRACKED IN TWO PLACES. PREFORMED A LEAK CHECK OF THE HEAT EXCHANGER AND FOUND LEAKS NOT ONLY FROM THE VISABLE CRACKS, BUT ALSO LEAKS INTERNAL TO THE HEAT EXCHANGER IN THE COOLING FIN AREA. REPLACED WITH A NEW HEAT EXCHANGER.