Message Name:

L BLEED DUCT AIR LEAK

Message Code:

B3-007016

A hot air leak has been detected in the LEFT BLEED DUCTING running from the Left Bleed Valve to the Cross Bleed Valve and the Left Flow Control Valve.

• Left Bleed Duct
• Left Bleed Valve
• Cross Bleed Valve
• Left Flow Control Valve (MPE3)
• Left (L) Bleed Loop Sensor 1 (MT67)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Full Throttle Blog/Forum Articles/Infoservice/Newsletter:

• Forum Article May 2013 - Challenger 300: Routing of the Bleed Air Detection Element on the Intermediate Pressure Valve - ATA 36-21

Flight Operation Notifications Manual (FONM): None

NOTES:

• Troubleshooting Guide for Bleed Loops
• Bleed Loop Routing and Visual Aid Guide

1. Locate the short circuit or leak using the Leak Event location function.

   1. Check for short circuit at the corresponding connector.
      NOTE: Before replacing a loop always look at the loop for routing, ensure loop is not too close to the plumbing or the bleed hole on a valve. Review AMM 36-21-00-992-801 for component location. See individual loops for specific routing information.
   2. Use a Tegam meter to check capacitance and inductance between the inner and outer conductor of the corresponding loop. Perform the impedance check per the Leak Detection How To.

Leak Event Location History

The Leak Event Location History will identify when the system posted a fault, what loop failed and a general location based on approximate fuselage/wing station and percentage location of the overheat condition.

The CH350 reports the name of the bleed loop and fuselage station or wing station and general location of the leak in percentage. A 0% location starts at the beginning of the loop and the end of the loop is 100% so a 5% indication will be 5% of the total loop length.
L BLEED LEAK

1. Once the percentage value is obtained from the MDC, refer to mapping tool representing all potential bleed leak locations in term of percentage, for each metered bleed air hole and LRU connections point. This will help to quickly troubleshoot source of the leak.hen a location is identified in the leak event location history, Inspect the plumbing for possible leaks.
2. If the leak can not be identified, perform the system functional check IAW AMM 36-21-00-710-801

Leak Detection Test

The test will check all of the loops the IASC is monitoring and pass or fail them. This test may fail if there is a lot of action going on in the IASC, retesting may pass the failed loops. This test is disabled with the wing heat system on. Perform the initiation (IBIT) test of the bleed air leak detection loops IAW AMM 36-21-00-740-801.

LH Bleed loop information

The test will identify if the respective LH loop has a short or open (>75 Ω). MT67 (LH system loop). Perform resistance checks on the applicable loop per AMM 36-21-00-760-801.