As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX ON FLIGHT 2277- WHEN LANDING GEAR SELECTED DOWN FOR LANDING, GEAR DID NOT EXTEND. DID GET RED UNSAFE LIGHTS AND LIGHT IN THE HANDLE. LEVELED OFF AND ADDED POWER TO GO AROUND AND GEAR CAME DOWN APPROXIMATELY 30 SECONDS AFTER ORIGINALLY SELECTED DOWN. GEAR DID NOT RETRACT ON GO AROUND. AIRCRAFT LANDED WITHOUT INCIDENT. REMOVED AND REPLACED LANDING GEAR SELECTOR VALVE. OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.