Date: 201706
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Light: Night
Aircraft: A320
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Climb
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Aircraft component: Aircraft Cooling System
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; First Officer
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Physiological - Other; Troubleshooting
Anomaly: Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Other / Unknown
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Aircraft Automation Overrode Flight Crew; Flight Crew Diverted; Flight Crew Landed As Precaution; General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: On climbout we received an ECAM for COND ZONE REGUL FAULT. Initially; only the primary channel had failed. Shortly after this the ECAM reoccurred and both the primary and secondary channels had failed. We sent an associated MRM code. With no ECAM steps to complete; we referenced the QRH and found that the notes indicated we should be able to maintain a reasonable cabin temperature in this configuration; albeit on the cool side (pack outputs of 68F and 50F were expected; per the notes). Flight attendants were notified and kept us up to date on cabin conditions and passenger mood. Maintenance was notified and asked for ideas on how to regain control of cabin temp (dispatch was copied). No ideas or reset procedures were available.During cruise; both pack output temps steadily decreased and the cabin temperature continued to drop. This was unexpected to me due to the QRH notes and seemed to indicate a triple failure; including all redundant modes. After evaluating the cabin temperature and passenger mood; combined with the observation that both pack output and cabin temps would likely continue to drop; we decided to divert and notified dispatch and ATC. We did not declare an emergency since cabin temps did not appear unsafe; albeit they were definitely uncomfortable. The selected station seemed the best option due to maintenance; passenger services/connections; and proximity along route of flight.On descent we encountered a new; unknown problem. A very loud sound of continuous rushing air was heard throughout the aircraft; but no new ECAMs or status messages appeared to indicate what the problem was. Communication on the flight deck became very difficult due to how loud it was. I notified ATC and dispatch of our emergency and this new; unknown issue. At first I was concerned about pressurization; but studying the systems pages revealed that pressurization was functioning normally and the bleed air/conditioned air status had not changed (other than pack output temps continuing to decrease way below QRH values; as previously noted). The loud air noise varied with thrust lever position. The cabin temperature was also dropping faster than before.The Captain performed a successful overweight landing and we taxied to the gate without further issues. The passengers were deplaned and re-accommodated in a timely fashion. The Captain and I remained behind to fully brief the maintenance team on all that we had encountered. I would like to commend the professionalism of all parties involved; especially our flight attendants.




Synopsis: A320 First Officer reported an issue with the packs that caused the cabin temperature to drop to uncomfortably cold. During their divert; the aircraft filled with loud rushing air making communication difficult.