Narrative:

When I [maintenance controller X] came on duty the left bleed leak warning was being reported by phone by the flight crew. I called outstation maintenance to come to the aircraft to try to find the cause of the indication. We checked the maintenance diagnostic computer (mdc) for evidence and found none but ran a bleed leak event location test. The results of the test indicated a leak or false indication in the APU bleed air duct between the APU bulkhead and the isolation valve at the crossover duct. The mechanic inspected the duct and bleed [overheat warning] loops and could not find any defects. We then ran the APU at the gate; supplying air for a considerable length of time and could not duplicate the fault. The aircraft was released with no faults found. An hour or more later the warning came back. The mechanic was still in the area so I had the crew shut down the APU and use an airstart to run the engines. My involvement ended at this point in the event because I became involved in some other problem. My comment to the maintenance operations and duty manager (mod) at this point was that I suggested we find another aircraft for the flight because we could not effectively troubleshoot this 'warning' problem without a 'break out box' and some other tooling and parts. I felt we were either proving a leak in the APU ducting or a false warning in that area at this point. The next thing I knew the APU was deferred and the aircraft was released.maintenance controller Z told me when I came in for work the next week that he had been requested to submit a report because the deferral of the APU was deemed inappropriate. There was a lot of discussion in the office between maintenance controller Z and the mod as to the correctness of that and I am not sure where that went. I could not find an acceptable deferral for this fault. The deferrals stipulated that the APU load control valve (lcv) had to function and in the warning condition; it is forced to 'close'; so in my opinion that is 'not working'.....this event transpired over several hours and there was a lot of conversation in the office about how to move the aircraft. My solution was to replace the aircraft and send a roadtrip because I do not feel that outstation maintenance can effectively troubleshoot a warning in this system without proper tooling and training. I guess I was overruled.I am submitting this ASRS report. My timeline is not firm and there were a lot of other problems at the time. And guess what? I came in to work today and we have the same problem on the same aircraft again. The only difference is the location of the aircraft. It is even showing the same locations again in the anti-ice leak detection controller (ailc) event location test. Maybe we have a bad ailc? Or we have an actual leak that we have not located yet. There is a significant lack of knowledge of this system in the maintenance control office and '0' experience working on the system other than maintenance controller Y and myself. Nobody wants to hear what I have to say about it. I am too conservative and not deemed a 'team player' when it comes to these kind of issues.it is my belief that any time a 'warning' occurs in this system it appears to me that if the system cannot be deferred; it cannot be troubleshot effectively by an untrained; ill equipped outstation mechanic 'looking it over' and signing it off. If the system is not deferrable then it should demand a roadtrip supported by qualified mechanics with proper training and proper equipment and tooling.

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Original NASA ASRS Text

Title: A Maintenance Controller reports about events surrounding an inappropriate deferral of an APU for an EICAS L BLEED LEAK WARNING on a CRJ-900 aircraft at an outstation gate. Controller also noted the significant lack of knowledge maintenance controllers have of the pneumatic system; the untrained; ill equipped outstation mechanics; and the lack of effective troubleshooting the cause of the EICAS warning.

Narrative: When I [Maintenance Controller X] came on duty the L BLEED LEAK WARNING was being reported by phone by the flight crew. I called outstation Maintenance to come to the aircraft to try to find the cause of the indication. We checked the Maintenance Diagnostic Computer (MDC) for evidence and found none but ran a Bleed Leak Event Location test. The results of the test indicated a leak or false indication in the APU bleed air duct between the APU bulkhead and the Isolation Valve at the Crossover duct. The Mechanic inspected the duct and bleed [Overheat Warning] loops and could not find any defects. We then ran the APU at the gate; supplying air for a considerable length of time and could not duplicate the fault. The aircraft was released with no faults found. An hour or more later the warning came back. The Mechanic was still in the area so I had the crew shut down the APU and use an airstart to run the engines. My involvement ended at this point in the event because I became involved in some other problem. My comment to the Maintenance Operations and Duty Manager (MOD) at this point was that I suggested we find another aircraft for the flight because we could not effectively troubleshoot this 'warning' problem without a 'break out box' and some other tooling and parts. I felt we were either proving a leak in the APU ducting or a false warning in that area at this point. The next thing I knew the APU was deferred and the aircraft was released.Maintenance Controller Z told me when I came in for work the next week that he had been requested to submit a report because the deferral of the APU was deemed inappropriate. There was a lot of discussion in the office between Maintenance Controller Z and the MOD as to the correctness of that and I am not sure where that went. I could not find an acceptable deferral for this fault. The deferrals stipulated that the APU Load Control Valve (LCV) had to function and in the warning condition; it is forced to 'close'; so in my opinion that is 'not working'.....This event transpired over several hours and there was a lot of conversation in the office about how to move the aircraft. My solution was to replace the aircraft and send a roadtrip because I do not feel that outstation Maintenance can effectively troubleshoot a warning in this system without proper tooling and training. I guess I was overruled.I am submitting this ASRS report. My timeline is not firm and there were a lot of other problems at the time. And guess what? I came in to work today and we have the same problem on the same aircraft again. The only difference is the location of the aircraft. It is even showing the same locations again in the Anti-Ice Leak Detection Controller (AILC) event location test. Maybe we have a bad AILC? Or we have an actual leak that we have not located yet. There is a significant lack of knowledge of this system in the Maintenance Control office and '0' experience working on the system other than Maintenance Controller Y and myself. Nobody wants to hear what I have to say about it. I am too conservative and not deemed a 'team player' when it comes to these kind of issues.It is my belief that any time a 'warning' occurs in this system it appears to me that if the system cannot be deferred; it cannot be troubleshot effectively by an untrained; ill equipped outstation Mechanic 'looking it over' and signing it off. If the system is not deferrable then it should demand a roadtrip supported by qualified mechanics with proper training and proper equipment and tooling.

Data retrieved from NASA's ASRS site 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.