Date: 202001
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Dusk
Aircraft: Regional Jet 900 (CRJ900)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Climb
Airspace: Class C ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Service/Access Door
Component problem: Improperly Operated; Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown; Time Pressure; Workload
Second reporter function: Pilot Flying; First Officer
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Automation Aircraft Other Automation
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport
Contributing factors: Aircraft; Procedure
Primary problem: Ambiguous

Narrative: It all started at Gate XX; when we noticed a 'Service door unlocked' indication on the door's page. We recycled closing the service door a couple times without success after which we made the entry in the logbook and called maintenance. Two maintenance personnel arrived within 5 minutes and started working on it; they ended up deferring the service door and associated ground valve. Maintenance struggled with their computer system and it wasn't until XB19Z that they returned with the logbook after leaving around XA40Z without leaving explanations. Dropped the brake at XB23Z; We requested XXR to expedite the departure with an off of XB41Z. In the climb; around 8;500 feet; a caution message 'Cabin Alt' came to our attention. We [advised ATC of] our intentions to return to the field; we requested vectors with time to run the QRH. The aircraft was not pressurizing and the manual control procedure ineffective; we completed the unpressurized procedure to make sure it would be unpressurized upon landing. All appropriate communications with ATC; dispatch; operations; the cabin; and a brief PA were made. We landed at 79;000 pounds with a rate of 300 ft/min. Arrived at Gate XY and entered the discrepancies in the maintenance logbook. As we walked off the aircraft for an aircraft swap; maintenance confirmed that the ground valve had not been correctly closed when following MEL directives.Identification: In flight by EICAS messageCause: The ground valve was not properly closed by maintenanceSuggestions: Stress with maintenance personnel the implications of their work.


Second narrative: The flight began at Gate XX with a FWD Service Door amber message that would not go away after the door was cycled closed several times. Maintenance was contacted via radio at XA07Z. They sent a crew out and arrived 5 minutes later. Once the maintenance team verified the problem; they decided to MEL the Service Door indication system. This MEL necessitated the MEL of the ground valve. Maintenance completed their work and returned the aircraft logbook to the Captain at XB19Z. We finished our checklists and were 'out' at XB23Z. We requested takeoff from XXR in order to minimize further delays for our passengers and were granted the request with a subsequent 'off' time of XB41Z. During the initial climb while communicating with ZZZ Departure; we received a CABIN ALT amber caution message on the EICAS. We decided to level the plane off and the Captain [advised ATC] and requested 9;000 feet and vectors in order to run the QRH. The Captain gave me the radios and controls while he ran the QRH. The aircraft was not pressurizing at all and the manual pressurization checklist did not solve the problem. The captain then ran the QRH directed unpressurized procedure to ensure the aircraft would remain unpressurized upon landing. The Captain contacted the FAs; Dispatch; Operations; and I updated ATC with pertinent information about our emergency. We set up the aircraft for return to ZZZ and landing on XXR and briefed the approach. We discussed that the Captain would land the aircraft due to the fact it would be an overweight landing. We exchanged the controls prior to intercepting the final approach course. The Captain landed the aircraft and taxied the aircraft to the gate without further issue. The landing was made at 79;000 lbs and at a decent rate of 300 ft/min. After arrival at Gate XY; the appropriate entries were made in the logbook; walk-around completed; and the Captain notified maintenance. Upon leaving the aircraft; maintenance informed us that the ground valve was not fully closed as it should have been when completing the MEL before pushback.The failure to fully close the ground valve caused the aircraft to not pressurize during flight.


Synopsis: CRJ-900 flight crew reported that the aircraft failed to pressurize during initial climb. The ground valve had not been fully closed by maintenance during work conducted on the aircraft prior to departure.