As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF PRESSURIZATION AUTO FAILED TO STBY. ATTEMPTED OPERATION IN STBY AND MANUAL. CABIN DIDN''T PRESSURIZE. FOUND PACK VALVE C/B POPPED. LEVELED AT 8,000 FT, CABIN ALT 8,000. PSI DIF. ISOLATED POPPING C/B TO R23 RELAY. REPLACED BOTH R23 AND R22 RELAYS. RESET C/B, RAN LT AND RT PACKS IN AUTO AND MANUAL. OPS OK.