As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A-C EXPERIENCING EQUIP COOLING FAULTS. V12 OVERBOARD EXHAUST VALVE FOUND TO BE STICKING IN THE PARTIALLY CLOSED POSITION. REPLACED V12 EXHAUST VALVE. DIDN'T SOLVE PROBLEM. :REMOVED & REPLACED EQUIPMENT COOLING OVERHEAT SWITCH. FOUND SUFFICIENT AIR SOURCE IN DUCTING.