As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TURNING ON R/PACK, HAD AN ACRID, SMOKEY SMELL TO COCKPIT. PACK TEMP APPROX 50C DUCT TEMP BELOW 20C. DUCT PRESS APPROX 32 PSI. TURNED PACK OFF FOR REMAINDER OF FLT. SMELL SUBSIDED. RAN ENG PER CHAPTER 5 OF 727 JET RUN HANDBOOK. PERF'D OPS CK OF R/PACK PER 727 MM CHAP 21 W/O NOTICEABLE ODOR OR SMOKEY SMELL OBSERVED. WILL REQ NO ACTION. OK TO CONTINUE.