As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CABIN PRESSURE WARNING ILLUMINATED AT FL 190. SLOW CABIN CLIMB RATE NOTED. PRESSURIZATION WAS CONTROLLED IN MANUAL MODE. DIVERTED FOR REPAIRS. FOUND HOLE IN RE-HEATER INLET DUCT, AND BYPASS VALVE OUTLET DUCT DISCONNECTED. PERFOMED ACFT PRESSURIZATION IAW TASK 21-60-00-863-801. NO WARNING OR DEFECTS NOTED. RETURNED TO SERVICE.