What was found
THE GASKET SEALING THIS VALVE TO THE DUCTING BLEW OUT. THE AIR GOING THROUGH THIS DUCT IN THIS AREA IS EXTREMELY HOT (BLEED AIR). THIS VALVE IS MADE OUT OF PLASTIC AND AFTER THE GASKET BLEW OUT, IT MELTED SEVERELY AROUND ITS MOUNTING BASE. THIS VALVE IS VERY HARD TO SEE AND GET AT. HOT AIR WAS ESCAPING INTO THE BACK OF THE AIRCRAFT. SUBMITTER SUGGESTS THESE VALVES NOT BE MADE OUT OF PLASTIC. PRESSURIZATION AND CONDITIONED AIR WAS AFFECTED BY THIS.