B757 Undifferentiated or Other Model
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 106.13; Flight Crew Total 28000; Flight Crew Type 1526.58
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Provided Assistance; Flight Crew Overcame Equipment Problem; Flight Crew Returned To Departure Airport; Flight Crew Took Evasive Action; Flight Crew Requested ATC Assistance / Clarification; General Maintenance Action; General Flight Cancelled / Delayed
Aircraft
FL350; the Auto Controller number 2 went INOP and the red Cabin Alt light illuminated. We ran the checklist and did a phone patch to [Name].  We elected to continue to ZZZZ. After fifteen minutes; the Cabin Altitude controller number 1 was not controllable. We switched to manual controller.  We ran the Cabin Auto Inop checklist.  Called Dispatch and returned to ZZZ.  We did [advise ATC] and descended to FL250. We ran the diversion guide checklist. First Officer flew the aircraft to a great landing into the sun.  She was very professional the entire flight and I am thankful she was my partner. She made many suggestions.
Flight departed ZZZ with no issues. About 1 hour into the flight; Flight Attendant reported losing the galley ovens. About 1:30 into the flight we got a Cabin Altitude Warning. Ran the QRH and switched from Auto 2 to Auto 1 controller. The cabin altitude went back down from 10;000 to about 8;000 and seemed stable. We contacted Dispatch and [Maintenance Control] and everyone agreed it was safe to continue to ZZZZ. After about 15 minutes the cabin altitude started increasing again and right before it hit 10;000 we switched to the Manual controller per the QRH. The cabin altitude was controllable again but we [advised ATC] and opted to turn around and go back to ZZZ. Completed the diversion checklist. We also felt more comfortable at a lower altitude and descended to FL250. Landed in ZZZ without any issues. Captain was very professional and as cool as the other side of a pillow during the entire event.
757 flight crew performed an air turn back after cabin pressure became uncontrollable.