Emb-135LR flight crew reported a pressurization problem during climbout.

Attributes
ACN	1701912
Time
Date	201911
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	EMB ERJ 135 ER/LR
Operating Under FAR Part	Part 135
Flight Phase	Climb
Flight Plan	IFR
Component
Aircraft Component	Pressurization System
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Events
Anomaly	Aircraft Equipment Problem Critical

Narrative:

Upon departing ZZZ; our plane reached 10;500 feet and flight crew's ears automatically popped. Upon diagnosing what happened; we noticed the cabin altitude rise into a red warning of 10;000+ feet and cabin rate went to f dashed lines in orange color. We leveled off right away at 11;000 feet; assessed the problem; and communicated with ATC (air traffic control) that we had a pressurization issue. ZZZ departure took us down to 10;000 feet fairly quickly. Once we got to 10;000 feet; ATC turned us around and vectored us for a xxr landing. The issue was diagnosed carefully by both cockpit crew; and while the captain PIC (pilot in command) started to problem solve; the sic (second in command) flew the plane and communicated with ATC. The plane arrived back in ZZZ safe and sound with no injuries.

Original NASA ASRS Text

Title: EMB-135LR flight crew reported a pressurization problem during climbout.

Narrative: Upon departing ZZZ; our plane reached 10;500 feet and flight crew's ears automatically popped. Upon diagnosing what happened; we noticed the cabin altitude rise into a red warning of 10;000+ feet and cabin rate went to f dashed lines in orange color. We leveled off right away at 11;000 feet; assessed the problem; and communicated with ATC (Air Traffic Control) that we had a pressurization issue. ZZZ Departure took us down to 10;000 feet fairly quickly. Once we got to 10;000 feet; ATC turned us around and vectored us for a XXR landing. The issue was diagnosed carefully by both cockpit crew; and while the Captain PIC (Pilot In Command) started to problem solve; the SIC (Second In Command) flew the plane and communicated with ATC. The plane arrived back in ZZZ safe and sound with no injuries.

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.