EMB ERJ 145 ER/LR
Aircraft Equipment Problem Less Severe
Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Departure Airport
Aircraft
Captain (Pilot Flying); First Officer (Pilot Monitoring). Flight departed ZZZ. During the climb out; passing 11;000 feet; First Officer (FO) noticed Cabin altitude was at 9300 feet and climbing. FO immediately verbalize what was going on. Immediately we stopped the climb; put out O2 masks on; notified ATC and requested an immediate descent below 10;000 feet. We were cleared to descent to 7500 feet. Once at 7500ft; we ran the QRH; switch from Auto Pressurization mode to Manual mode (Per QRH). Initially it appears to be pressurizing on Manual mode; but then we lost the cabin altitude reading; it went to amber dashes. We (as a flight crew) made the decision to return to ZZZ. We entered a holding pattern SW of ZZZ to burn fuel (get close to Landing Weight) and run the Diversion Guidance (on the FRG). We hold for about 30 min. While at the holding pattern we contact Flight Attendants (FA); Dispatch; Maintenance Control and made a PA. We ran the appropriate checklists and got ready for an approach in ZZZ. We landed safely and uneventfully in ZZZ (on Manual Pressurization mode and with cabin altitude indicating amber dashes). Once at the gate; the FA was unable to open the main cabin door. We realized we were still pressurized so we dumped the cabin. FA opened the main cabin door and passengers deplaned normally.
EMB-145 Captain reported a pressurization problem during climb.