Narrative:

On departure; we noticed the pressurization was not working as expected. A high climb rate was observed on the vsi and upon further scanning; we noticed the equipment door light illuminated. I asked to level at 7000 ft which was our clearance and asked for an initial heading for a return to mia. We were given a westerly heading and to keep ATC informed of our needs. We ran our QRH checklist and determined the aircraft was not pressurizing due to the equipment door. I asked for a return to runway 9 and we were given a descent and vectors to the runway. As we approached runway 9; the controller said we were overtaking a light aircraft and asked us if we could use runway 8R; so we switched over and landed uneventfully on runway 8R. I did not declare an emergency because I felt we had analyzed the problem properly and were able to return without further problems and we were not overweight for landing. Supplemental information from acn 771983: maintenance personnel advised that the east&east door was opened and was most likely the cause of the aircraft not pressurizing. The passenger were deplaned; the east&east door secured and a pressurization check of the aircraft was conducted. With the pressurization check complete and all doors secured; the passenger were boarded and the trip continued without incident. During walkaround no doors or hatches were opened. All checklists were initiated and all items completed.

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Original NASA ASRS Text

Title: B737-800 ACCESS DOOR WAS NOT SECURED; AND ACFT FAILED TO PRESSURIZE AFTER TKOF. FLT RETURNED TO DEP ARPT.

Narrative: ON DEP; WE NOTICED THE PRESSURIZATION WAS NOT WORKING AS EXPECTED. A HIGH CLB RATE WAS OBSERVED ON THE VSI AND UPON FURTHER SCANNING; WE NOTICED THE EQUIP DOOR LIGHT ILLUMINATED. I ASKED TO LEVEL AT 7000 FT WHICH WAS OUR CLRNC AND ASKED FOR AN INITIAL HDG FOR A RETURN TO MIA. WE WERE GIVEN A WESTERLY HDG AND TO KEEP ATC INFORMED OF OUR NEEDS. WE RAN OUR QRH CHKLIST AND DETERMINED THE ACFT WAS NOT PRESSURIZING DUE TO THE EQUIP DOOR. I ASKED FOR A RETURN TO RWY 9 AND WE WERE GIVEN A DSCNT AND VECTORS TO THE RWY. AS WE APCHED RWY 9; THE CTLR SAID WE WERE OVERTAKING A LIGHT ACFT AND ASKED US IF WE COULD USE RWY 8R; SO WE SWITCHED OVER AND LANDED UNEVENTFULLY ON RWY 8R. I DID NOT DECLARE AN EMER BECAUSE I FELT WE HAD ANALYZED THE PROB PROPERLY AND WERE ABLE TO RETURN WITHOUT FURTHER PROBS AND WE WERE NOT OVERWT FOR LNDG. SUPPLEMENTAL INFO FROM ACN 771983: MAINT PERSONNEL ADVISED THAT THE E&E DOOR WAS OPENED AND WAS MOST LIKELY THE CAUSE OF THE ACFT NOT PRESSURIZING. THE PAX WERE DEPLANED; THE E&E DOOR SECURED AND A PRESSURIZATION CHK OF THE ACFT WAS CONDUCTED. WITH THE PRESSURIZATION CHK COMPLETE AND ALL DOORS SECURED; THE PAX WERE BOARDED AND THE TRIP CONTINUED WITHOUT INCIDENT. DURING WALKAROUND NO DOORS OR HATCHES WERE OPENED. ALL CHKLISTS WERE INITIATED AND ALL ITEMS COMPLETED.

Data retrieved from NASA's ASRS site as of May 2009 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.