As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RECEIVED LH PACK HI PRESS DURING CLIMB WHILE TRANSFERRING BLEEDS. C/W QRH, MESSAGE REMAINED ON. ALSO HAD LH PACK FAIL ON OVERHEAD. *****AIRCRAFT REMOVED FROM SERVICE. FLT 6274 AIR RETURNED DUE TO MECHANICAL PROBLEMS-DECLARED EMER. ALSO DECLARED EMER DUE TO 2EA PX MEDICAL ISSUES**** R&R OF LH PRSOV FILTER IAW AWAC SUP 06-039A. OPS CHECK GOOD.