Narrative:

While taxiing from gate to runway xxl; I called for the before takeoff checklist to the line; which was completed. When #5 for takeoff I called for the delayed engine start checklist and engine #1 was started. When #3 for takeoff I called for the final items; which were completed. The takeoff and climb was normal and I was hand flying while we were given multiple heading and altitude changes. While passing 13;000 feet on a clearance from 10;000 to 14;000 feet we heard the cabin altitude warning horn. After the 'startle affect' we both noticed the cabin altitude was reading 10;000 feet and that both packs were in the off position. The isolation valve was closed and both engine and APU bleeds were on (the same valve position the first officer had used for the delayed engine start). The first officer reset the a/C panel to the correct positions and I was surprised of the delayed re-pressurization so I called to don the oxygen mask and run the QRH.when the cabin altitude warning horn checklist was completed I told the first officer to contact ATC of our situation and that we need to descend. While the first officer was trying to contact ATC I began a descent from 14;000 to 10;000 feet with the throttle at idle and speed brake deployed. The first officer was having difficulty with the ATC call because of frequency congestion; the O2 mask was interfering with his personal headset; and we did not have the O2 switch in mask. Once we advised ATC that we lost pressurization and were descending to 10;000 feet; ATC cleared us to 10;000 feet and turn to a heading 080. We then ran the QRH cabin altitude off schedule descent checklist and I then asked the first officer to contact the flight attendants and ask if the passenger O2 masks had deployed; and they had not.now that the checklists were complete; the aircraft was properly configured and pressurized; we advised ATC that we would like to continue to our destination but at 250 knots so that we can call company dispatch and [maintenance control] and advise them of our situation. The first officer contacted arinc and got a phone patch to dispatch. We advised dispatch and [maintenance control] of our unintentional unpressurized takeoff and climb and that everything [was] now normal. With all in agreement; we continued to [destination].during debrief the first officer could not explain why he turned the #2 engine pack to off on the delayed engine start and why we both missed the a/C and pressurization and recall items on the checklists. I have a personal procedure to check the a/C panel when the a/C and pressurization item is called on the final items checklist; but I may have been distracted and didn't.

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Original NASA ASRS Text

Title: Boeing 737 Captain reported that the aircraft had not pressurized due to a misconfiguration of the pressurization system panel.

Narrative: While taxiing from gate to Runway XXL; I called for the Before Takeoff checklist to the line; which was completed. When #5 for takeoff I called for the Delayed Engine Start checklist and engine #1 was started. When #3 for takeoff I called for the Final Items; which were completed. The takeoff and climb was normal and I was hand flying while we were given multiple heading and altitude changes. While passing 13;000 feet on a clearance from 10;000 to 14;000 feet we heard the Cabin Altitude warning horn. After the 'startle affect' we both noticed the Cabin Altitude was reading 10;000 feet and that both PACKs were in the OFF position. The Isolation Valve was closed and both engine and APU bleeds were ON (the same valve position the First Officer had used for the delayed engine start). The First Officer reset the A/C panel to the correct positions and I was surprised of the delayed re-pressurization so I called to don the oxygen mask and run the QRH.When the Cabin Altitude Warning Horn checklist was completed I told the First Officer to contact ATC of our situation and that we need to descend. While the First Officer was trying to contact ATC I began a descent from 14;000 to 10;000 feet with the throttle at idle and speed brake deployed. The First Officer was having difficulty with the ATC call because of frequency congestion; the O2 mask was interfering with his personal headset; and we did not have the O2 switch in mask. Once we advised ATC that we lost pressurization and were descending to 10;000 feet; ATC cleared us to 10;000 feet and turn to a heading 080. We then ran the QRH Cabin Altitude Off Schedule Descent checklist and I then asked the First Officer to contact the Flight Attendants and ask if the passenger O2 masks had deployed; and they had not.Now that the checklists were complete; the aircraft was properly configured and pressurized; we advised ATC that we would like to continue to our destination but at 250 knots so that we can call company Dispatch and [Maintenance Control] and advise them of our situation. The First Officer contacted ARINC and got a phone patch to Dispatch. We advised Dispatch and [Maintenance Control] of our unintentional unpressurized takeoff and climb and that everything [was] now normal. With all in agreement; we continued to [destination].During debrief the First Officer could not explain why he turned the #2 engine PACK to OFF on the Delayed Engine Start and why we both missed the A/C and pressurization and recall items on the checklists. I have a personal procedure to check the A/C panel when the A/C and pressurization item is called on the Final Items checklist; but I may have been distracted and didn't.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.