As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 6299 - IAD-BOS - DURING CLIMB, MADE UNSCHEDULED LANDING DUE TO RIGHT DUCT WARNING LGIHT ILLUMINATED IN FLIGHT. AIRCRAFT RETURNED TO GATE AT IAD WITH NO FURTHER PROBLEMS. MAINTENANCE INSPECTED AND REMOVED AND REPLACED TEMP VALVE DUCT O-RINGS, OPS CHECK OK. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)