As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LYH-IAD - FLT 902 - DURING CLIMB, AIRCRAFT MADE AN UNSCHEDULED LANDING DUE TO PRESSURIZATION INOP. AIRCRAFT RETURNED TO GATE WITH NO FURTHER PROBLEMS. MAINTENANCE INSPECTED AND SECURED LOOSE DUCT ON LEFT ACM, OPS CHECK OK. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)