EMB ERJ 145 ER/LR
Flight Crew Air Transport Pilot (ATP)
Flight Crew Total 5000
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural MEL / CDL
Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport
MEL; Aircraft
Aircraft had MEL of Pack 2. While climbing out Pack 1 valve closed (advisory message) and would not remain open after following QRH procedures; rendering us with no air conditioning or pressurization systems found by searching the EICAS for cabin altitude climb rate. We contacted ATC; stopped the climb approximately FL180; started a descent; and started a return to ZZZ. In troubleshooting the problem; Pack 2 was able to provide pressurization and cooling during our descent as temperatures in cockpit and cabin were high. Utilized Pack 2 although it was MEL. During the logbook review; the Pack was MEL because of the valve closing; and a reason why I attempted to operate it and see if it would assist us in our situation. Due to the quick action of the flight crew; the cabin altitude was never out of tolerances and the only discomfort was temperature for passengers and the delay; as we were down to ten thousand feet very quickly. CRM was a great part; as the entire crew was able to return the aircraft safely to the ground in minimal time.
EMB145 Captain reported on climb out with one air conditioning pack deferred; the other pack failed. Captain reported crew ran QRH procedure and used deferred pack to provide pressurization and cooling on return to departure airport.