Narrative:

On flight to ZZZ at FL350; we received a right bleed duct warning. We were about 45 minutes south of ZZZ. We had just requested and received a descent to FL310 to burn off extra fuel (because I calculated that we would be over maximum landing weight 75;100 pounds). Additionally; we had the engine and wing ice on to increase our fuel burn. I began chapter items; and checked the ecs synoptic and found the ducting adjacent the right engine colored red. I asked first officer to request a lower altitude; and we were given FL250 then FL240. Soon after; we got a call from the cabin telling us that the floor in the back of the aft cabin was 'hot;' and there was a burning plastic smell. I said I'd get right back to them after a checklist and said to call if it got worse and asked if there was smoke (there was not). The red warning soon turned to an amber caution on the primary page; and I noticed a pressure change in my ears (steady and more than normal). I checked the ecs page again and found both pressure regulating shutoff valve's had closed; and the cabin altitude was rising. I continued the chapter items for manual bleed procedure; to reestablish pressurization from the left engine with no success. Then I started the APU and tried to reestablish pressurization according to chapter with no success. It appeared that the system 'wanted' to keep the left pressure regulating shutoff valve and APU closed; and that was where we should leave it. We requested 10;000 ft; received 10;000 ft; and began a fairly steep descent. Somewhere near 10;000 ft the cabin altitude reached 8;500 ft and we received the 'cabin altitude' amber caution. First officer requested that we do the chapter items for this caution. I looked at the checklist and the first item was bleed valves&automatic. I felt that this checklist was a bad idea because the system had already 'refused' to open the left engine pressure regulating shutoff valve or the APU with the other chapter items (manual bleed procedure); so I chose not to complete these items. At some point; we advised ATC that we had a pressurization problem. Somewhere in the mix; I contacted dispatch and advised them of the problem and said we wanted to divert. In addition to the hot floor; with the pressure regulating shutoff valves closed; we did not have engine cowl anti-ice; and there was a reported layer of clouds with potential icing in ZZZ. Dispatch suggested ZZZ1 and we began the diversion (it was pretty clear over ZZZ1). I called the cabin again and was told that the floor was a little better and the smell was less. (I assume because the bleeds had closed). I think this is also where I told the flight attendants that we planned to divert to ZZZ1 and we discussed a landing. Around this time we received an ACARS message suggesting ZZZ instead of ZZZ1 because the icing/cloud layer was dissipating (now thin and scattered) with improving news from the cabin about the floor and smell; and a dissipating cloud layer in ZZZ; we decided to continue for ZZZ. I made an announcement over the PA about the pressurization issue and that we had planned to divert to ZZZ1; but weather in ZZZ had improved and we would be continuing to ZZZ. We then landed without further event arriving at the gate 15 minutes beyond scheduled arrival. I wrote up the plane and spoke with the mechanic about the issue. I spoke with the mechanic after the day after the event; and he said that 2 sensor wires had somehow come in contact with each other; causing the problem.

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Original NASA ASRS Text

Title: CRJ900 Captain reports RIGHT BLEED LEAK at FL350 and eventual loss of pressurization due to automatic closing of the Pressure Regulating Shutoff Valve's. Crew is able to continue to destination at 10;000 FT; unpressurized.

Narrative: On flight to ZZZ at FL350; we received a Right Bleed Duct warning. We were about 45 minutes south of ZZZ. We had just requested and received a descent to FL310 to burn off extra fuel (because I calculated that we would be over maximum landing weight 75;100 LBS). Additionally; we had the engine and wing ice on to increase our fuel burn. I began chapter items; and checked the ECS synoptic and found the ducting adjacent the right engine colored red. I asked First Officer to request a lower altitude; and we were given FL250 then FL240. Soon after; we got a call from the cabin telling us that the floor in the back of the aft cabin was 'hot;' and there was a burning plastic smell. I said I'd get right back to them after a checklist and said to call if it got worse and asked if there was smoke (there was not). The red warning soon turned to an amber caution on the primary page; and I noticed a pressure change in my ears (steady and more than normal). I checked the ECS page again and found both Pressure Regulating Shutoff Valve's had closed; and the cabin altitude was rising. I continued the Chapter items for manual bleed procedure; to reestablish pressurization from the left engine with no success. Then I started the APU and tried to reestablish pressurization according to Chapter with no success. It appeared that the system 'wanted' to keep the left Pressure Regulating Shutoff Valve and APU closed; and that was where we should leave it. We requested 10;000 FT; received 10;000 FT; and began a fairly steep descent. Somewhere near 10;000 FT the cabin altitude reached 8;500 FT and we received the 'Cabin Altitude' amber caution. First Officer requested that we do the Chapter items for this caution. I looked at the checklist and the first item was Bleed Valves&Automatic. I felt that this checklist was a bad idea because the system had already 'refused' to open the left engine Pressure Regulating Shutoff Valve or the APU with the other Chapter items (manual bleed procedure); so I chose not to complete these items. At some point; we advised ATC that we had a pressurization problem. Somewhere in the mix; I contacted Dispatch and advised them of the problem and said we wanted to divert. In addition to the hot floor; with the Pressure Regulating Shutoff Valves closed; we did not have engine cowl anti-ice; and there was a reported layer of clouds with potential icing in ZZZ. Dispatch suggested ZZZ1 and we began the diversion (it was pretty clear over ZZZ1). I called the cabin again and was told that the floor was a little better and the smell was less. (I assume because the bleeds had closed). I think this is also where I told the Flight Attendants that we planned to divert to ZZZ1 and we discussed a landing. Around this time we received an ACARS message suggesting ZZZ instead of ZZZ1 because the icing/cloud layer was dissipating (now thin and scattered) with improving news from the cabin about the floor and smell; and a dissipating cloud layer in ZZZ; we decided to continue for ZZZ. I made an announcement over the PA about the pressurization issue and that we had planned to divert to ZZZ1; but weather in ZZZ had improved and we would be continuing to ZZZ. We then landed without further event arriving at the gate 15 minutes beyond scheduled arrival. I wrote up the plane and spoke with the Mechanic about the issue. I spoke with the mechanic after the day after the event; and he said that 2 sensor wires had somehow come in contact with each other; causing the problem.

Data retrieved from NASA's ASRS site as of May 2009 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.