# Kidde Aerospace Service Bulletin CFD-26-1: Revision 6

- Rights: © KIDDE TECHNOLOGIES, INC. Filed by the FAA in regulations.gov docket FAA-2022-1483; AD 2023-16-03 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Kidde Aerospace Service Bulletin CFD-26-1](https://openairdocs.org/service-documents/kidde/cfd26-1.md)
- Title as filed: CFD-26-1 Rev 6
- Pages: 36
- PDF: https://openairdocs.org/files/sha256/a6/0e/a60e8ff6dc37bbe8536b169c9d13f4a9aa6ae93a523ebee301989d6efd2d9beb
- Page: https://openairdocs.org/service-documents/kidde/cfd26-1/file/a60e8ff6dc37

## Text

Some pages are OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
Transmittal Sheet 
Summary
This service bulletin provides a bench test procedure for CFD’s to verify proper operation. 
Failed units will be replaced by Kidde Aerospace and Defense.
This is revision 6 of Service Bulletin CFD-26-1 for the CFD. This revision updates an incorrect 
reference to a service bulletin, corrects a logical operator in the text to match the datasheet, 
corrects wording for clarification purposes within the service bulletin, corrects a part number 
in the reference section, adds new part numbers in the reference section, corrects a salt type 
example for Heat Temperature Settings, and other typographical errors.
Black bars in the margins indicate the changes.
Replace revision 5 with this revision.
Service Bulletin Revision History
REVISION DATE OF RELEASE
Initial Release (IR) May 7, 2021
Revision 1 May 13, 2021
Revision 2 June 3, 2021
Revision 3 July 23, 2021
Revision 4 October 7, 2021
Revision 5 January 14, 2022
Revision 6 February 28, 2022
Subject to the EAR, ECCN 9E991
.
The data in this document were developed only to maintain systems and/or parts manufactured by or for Collins Aerospace 
or approved by Collins Aerospace. The data may not be applicable to any other systems and/or parts, regardless of their 
apparent similarity to systems and/or parts manufactured by or for Collins Aerospace or approved by Collins Aerospace. 
Do not rely in any way on data in this document to maintain or otherwise support systems and/or parts that were not 
manufactured by or for Collins Aerospace or approved by Collins Aerospace without evidence that the Federal Aviation 
Administration or other regulatory agency has determined that the data in this document is valid for such use.
Collins Aerospace assumes no liability whatsoever, whether contractual, warranty, tort or otherwise, for unauthorized 
alteration or alterations not performed in accordance with Collins Aerospace approved procedures.
February 28/22 CFD-26-1
523-0832620

### Page 2

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
1. PLANNING INFORMATION
A. Effectivity
This Service Bulletin (SB) is applicable for CFD Units.
PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE
04-31102-026A Before A2105 04-90001-D018 Before A2105 04-90025-9394R Before A2105
04-31102-031A Before A2105 04-90001-D044 Before A2105 04-90025-9406C Before A2105
04-31102-035A Before A2105 04-90001-D046 Before A2105 04-90025-9406R Before A2105
04-31102-036A Before A2105 04-90011-030A Before A2105 04-90026-9204A Before A2105
04-31102-041A Before A2105 04-90011-060A Before A2105 04-90026-9206A Before A2105
04-31102-044A Before A2105 04-90011-180A Before A2105 04-90028-9046A Before A2105
04-31102-058A Before A2105 04-90022-9100C Before A2105 04-90028-9050A Before A2105
04-31102-059A Before A2105 04-90022-9115A Before A2105 04-90028-9051A Before A2105
04-31102-061A Before A2105 04-90022-9200A Before A2105 04-90028-9052A Before A2105
04-31102-062A Before A2105 04-90022-9200C Before A2105 04-90028-9059A Before A2105
04-31102-065A Before A2105 04-90022-9200M Before A2105 04-90028-9062A Before A2105
04-31102-067A Before A2105 04-90022-9250C Before A2105 04-90028-9063A Before A2105
04-31102-079A Before A2105 04-90022-9300M Before A2105 04-90028-9065A Before A2105
04-31102-082A Before A2105 04-90022-9385M Before A2105 04-90028-9067A Before A2105
04-31102-084A Before A2105 04-90024-901 Before A2105 04-90028-9070A Before A2105
04-31102-085A Before A2105 04-90025-9043C Before A2105 04-90028-9071A Before A2105
04-31102-087A Before A2105 04-90025-9046C Before A2105 04-90028-9073A Before A2105
04-31102-090A Before A2105 04-90025-9117C Before A2105 04-90028-9075A Before A2105
04-31102-100A Before A2105 04-90025-9118C Before A2105 04-90028-9076A Before A2105
04-31102-102A Before A2105 04-90025-9121C Before A2105 04-90028-9078A Before A2105
04-31102-106A Before A2105 04-90025-9136A Before A2105 04-90028-9081A Before A2105
04-31102-107N Before A2105 04-90025-9148C Before A2105 04-90028-9100A Before A2105
04-31102-108N Before A2105 04-90025-9156A Before A2105 04-90028-9103A Before A2105
04-31102-109A Before A2105 04-90025-9157C Before A2105 04-90028-9107A Before A2105
04-31102-111A Before A2105 04-90025-9181A Before A2105 04-90028-9109A Before A2105
04-31102-114A Before A2105 04-90025-9181R Before A2105 04-90028-9111A Before A2105
04-31102-116A Before A2105 04-90025-9186A Before A2105 04-90028-9116A Before A2105
04-31102-119A Before A2105 04-90025-9186R Before A2105 04-90028-9117A Before A2105
04-31102-121A Before A2105 04-90025-9191C Before A2105 04-90028-9120A Before A2105
04-31102-124A Before A2105 04-90025-9199A Before A2105 04-90028-9123A Before A2105
04-31102-125A Before A2105 04-90025-9204C Before A2105 04-90028-9128A Before A2105
04-31102-125N Before A2105 04-90025-9212C Before A2105 04-90028-9129A Before A2105
04-31102-128A Before A2105 04-90025-9222A Before A2105 04-90028-9130A Before A2105
04-31102-129N Before A2105 04-90025-9256R Before A2105 04-90028-9133A Before A2105
04-31102-130A Before A2105 04-90025-9259A Before A2105 04-90028-9135A Before A2105
04-31102-132A Before A2105 04-90025-9259R Before A2105 04-90028-9136A Before A2105
04-31102-133A Before A2105 04-90025-9280C Before A2105 04-90028-9139A Before A2105
04-31102-135A Before A2105 04-90025-9287C Before A2105 04-90028-9140A Before A2105
04-31102-138A Before A2105 04-90025-9287R Before A2105 04-90028-9141A Before A2105
04-31102-140A Before A2105 04-90025-9294R Before A2105 04-90028-9142A Before A2105
04-31102-153A Before A2105 04-90025-9308A Before A2105 04-90028-9147A Before A2105
04-31102-154A Before A2105 04-90025-9318A Before A2105 04-90028-9150A Before A2105
04-31102-162A Before A2105 04-90025-9328A Before A2105 04-90028-9153A Before A2105
04-31102-164A Before A2105 04-90025-9347A Before A2105 04-90028-9155A Before A2105
04-31102-171A Before A2105 04-90025-9347C Before A2105 04-90028-9157A Before A2105
04-31102-176A Before A2105 04-90025-9394C Before A2105 04-90028-9165A Before A2105
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 1 of 33

### Page 3

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE
04-90028-9169A Before A2105 04-90030-9109D Before A2105 04-90030-9370A Before A2105
04-90028-9170A Before A2105 04-90030-9110A Before A2105 04-90030-9373A Before A2105
04-90028-9177A Before A2105 04-90030-9114A Before A2105 04-90031-9272A Before A2105
04-90028-9183A Before A2105 04-90030-9114C Before A2105 04-90031-9274A Before A2105
04-90028-9190A Before A2105 04-90030-9115A Before A2105 04-90031-9309A Before A2105
04-90028-9202A Before A2105 04-90030-9115C Before A2105 04-90031-9311A Before A2105
04-90028-9204A Before A2105 04-90030-9117A Before A2105 04-90031-9313A Before A2105
04-90028-9206A Before A2105 04-90030-9121A Before A2105 04-90031-9315A Before A2105
04-90028-9208A Before A2105 04-90030-9121C Before A2105 04-90032-901 Before A2105
04-90028-9211A Before A2105 04-90030-9124A Before A2105 04-90032-902 Before A2105
04-90028-9214A Before A2105 04-90030-9131A Before A2105 04-90033-9058A Before A2105
04-90028-9217A Before A2105 04-90030-9150A Before A2105 04-90033-9307A Before A2105
04-90028-9220A Before A2105 04-90030-9154A Before A2105 04-90033-9307F Before A2105
04-90028-9224A Before A2105 04-90030-9156A Before A2105 04-90034-9050A Before A2105
04-90028-9227A Before A2105 04-90030-9161A Before A2105 04-90034-9061A Before A2105
04-90028-9230A Before A2105 04-90030-9164A Before A2105 04-90034-9069A Before A2105
04-90028-9232A Before A2105 04-90030-9171A Before A2105 04-90034-9091A Before A2105
04-90028-9234A Before A2105 04-90030-9193A Before A2105 04-90034-9093A Before A2105
04-90028-9244A Before A2105 04-90030-9201A Before A2105 04-90034-9103A Before A2105
04-90028-9249A Before A2105 04-90030-9203A Before A2105 04-90034-9110A Before A2105
04-90028-9251A Before A2105 04-90030-9205A Before A2105 04-90034-9122A Before A2105
04-90028-9255A Before A2105 04-90030-9209A Before A2105 04-90034-9155A Before A2105
04-90028-9258A Before A2105 04-90030-9214A Before A2105 04-90034-9163A Before A2105
04-90028-9263A Before A2105 04-90030-9223A Before A2105 04-90034-9171A Before A2105
04-90028-9265A Before A2105 04-90030-9249A Before A2105 04-90034-9183A Before A2105
04-90028-9268A Before A2105 04-90030-9249C Before A2105 04-90034-9190A Before A2105
04-90028-9272A Before A2105 04-90030-9252A Before A2105 04-90034-9192A Before A2105
04-90028-9276A Before A2105 04-90030-9252C Before A2105 04-90034-9197A Before A2105
04-90028-9283A Before A2105 04-90030-9262A Before A2105 04-90034-9205A Before A2105
04-90028-9285A Before A2105 04-90030-9273A Before A2105 04-90034-9211A Before A2105
04-90028-9293A Before A2105 04-90030-9283A Before A2105 04-90034-9214A Before A2105
04-90028-9295A Before A2105 04-90030-9292A Before A2105 04-90034-9218A Before A2105
04-90028-9298A Before A2105 04-90030-9294A Before A2105 04-90034-9224A Before A2105
04-90028-9299A Before A2105 04-90030-9296A Before A2105 04-90034-9226A Before A2105
04-90028-9310A Before A2105 04-90030-9303A Before A2105 04-90034-9231A Before A2105
04-90028-9316A Before A2105 04-90030-9307A Before A2105 04-90034-9236A Before A2105
04-90028-9339A Before A2105 04-90030-9309A Before A2105 04-90034-9237A Before A2105
04-90030-9069C Before A2105 04-90030-9311A Before A2105 04-90034-9248A Before A2105
04-90030-9072C Before A2105 04-90030-9313A Before A2105 04-90034-9253A Before A2105
04-90030-9089C Before A2105 04-90030-9317A Before A2105 04-90034-9263A Before A2105
04-90030-9089D Before A2105 04-90030-9320A Before A2105 04-90034-9266A Before A2105
04-90030-9095D Before A2105 04-90030-9323A Before A2105 04-90034-9272A Before A2105
04-90030-9096A Before A2105 04-90030-9325A Before A2105 04-90034-9282A Before A2105
04-90030-9099D Before A2105 04-90030-9328A Before A2105 04-90034-9288A Before A2105
04-90030-9100A Before A2105 04-90030-9337A Before A2105 04-90034-9300A Before A2105
04-90030-9100D Before A2105 04-90030-9343A Before A2105 04-90034-9304A Before A2105
04-90030-9103A Before A2105 04-90030-9344A Before A2105 04-90034-9307A Before A2105
04-90030-9104D Before A2105 04-90030-9352A Before A2105 04-90034-9314A Before A2105
04-90030-9107A Before A2105 04-90030-9352C Before A2105 04-90034-9326A Before A2105
04-90030-9107C Before A2105 04-90030-9356A Before A2105 04-90034-9332A Before A2105
04-90030-9107D Before A2105 04-90030-9356C Before A2105 04-90034-9347A Before A2105
04-90030-9108A Before A2105 04-90030-9358A Before A2105 04-90034-9356A Before A2105
04-90030-9108C Before A2105 04-90030-9359A Before A2105 04-90034-9357A Before A2105
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 2 of 33

### Page 4

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE
04-90034-9368A Before A2105 1052002-186C Before A2105 1052003-238U Before A2105
04-90034-9380A Before A2105 1052002-188A Before A2105 1052003-240U Before A2105
04-90034-9394A Before A2105 1052002-210C Before A2105 1052003-242U Before A2105
04-90034-9396A Before A2105 1052002-221C Before A2105 1052003-278U Before A2105
04-90034-9401A Before A2105 1052002-291C Before A2105 1052003-288U Before A2105
04-90034-9405A Before A2105 1052002-298C Before A2105 1052003-290U Before A2105
04-90034-9409A Before A2105 1052002-312A Before A2105 1052003-335U Before A2105
04-90034-9419A Before A2105 1052002-319A Before A2105 1052003-342U Before A2105
04-90041-9046C Before A2105 1052002-322A Before A2105 1052003-354U Before A2105
04-90041-9152C Before A2105 1052002-327A Before A2105 1052003-373U Before A2105
1052002-053A Before A2105 1052002-345C Before A2105 1052003-376U Before A2105
1052002-055C Before A2105 1052002-349C Before A2105 1052003-399U Before A2105
1052002-056A Before A2105 1052002-362A Before A2105 1052003-410U Before A2105
1052002-058C Before A2105 1052002-368A Before A2105 1052003-416U Before A2105
1052002-059A Before A2105 1052003-050M Before A2105 1052003-441U Before A2105
1052002-062C Before A2105 1052003-056U Before A2105 1052003-447U Before A2105
1052002-063A Before A2105 1052003-069M Before A2105 1052009-070D Before A2105
1052002-073C Before A2105 1052003-077M Before A2105 1052009-071D Before A2105
1052002-074C Before A2105 1052003-100A Before A2105 1052009-072D Before A2105
1052002-077C Before A2105 1052003-105M Before A2105 1052009-073D Before A2105
1052002-079C Before A2105 1052003-107M Before A2105 1052009-085A Before A2105
1052002-081C Before A2105 1052003-108A Before A2105 1052009-088A Before A2105
1052002-083D Before A2105 1052003-109M Before A2105 1052009-090D Before A2105
1052002-084C Before A2105 1052003-110M Before A2105 1052009-091D Before A2105
1052002-085C Before A2105 1052003-110U Before A2105 1052009-093D Before A2105
1052002-089D Before A2105 1052003-115A Before A2105 1052009-094A Before A2105
1052002-108A Before A2105 1052003-116M Before A2105 1052009-094D Before A2105
1052002-110C Before A2105 1052003-120M Before A2105 1052009-098A Before A2105
1052002-113C Before A2105 1052003-123A Before A2105 1052009-122D Before A2105
1052002-116C Before A2105 1052003-130U Before A2105 1052009-123D Before A2105
1052002-119A Before A2105 1052003-136U Before A2105 1052009-124D Before A2105
1052002-120C Before A2105 1052003-155M Before A2105 1052009-125D Before A2105
1052002-122A Before A2105 1052003-158M Before A2105 1052009-143R Before A2105
1052002-125C Before A2105 1052003-163M Before A2105 1052009-144R Before A2105
1052002-127C Before A2105 1052003-178U Before A2105 1052009-165A Before A2105
1052002-129A Before A2105 1052003-182U Before A2105 1052009-168A Before A2105
1052002-135C Before A2105 1052003-183U Before A2105 1052009-175A Before A2105
1052002-136A Before A2105 1052003-184U Before A2105 1052009-180A Before A2105
1052002-144A Before A2105 1052003-188U Before A2105 1052009-182A Before A2105
1052002-147C Before A2105 1052003-198U Before A2105 1052009-185A Before A2105
1052002-149C Before A2105 1052003-200U Before A2105 1052009-190A Before A2105
1052002-150C Before A2105 1052003-202U Before A2105 1052009-212R Before A2105
1052002-152C Before A2105 1052003-204M Before A2105 1052009-213A Before A2105
1052002-154C Before A2105 1052003-208M Before A2105 1052009-213R Before A2105
1052002-160A Before A2105 1052003-210U Before A2105 1052009-214A Before A2105
1052002-165C Before A2105 1052003-215U Before A2105 1052009-214R Before A2105
1052002-171A Before A2105 1052003-216U Before A2105 1052009-215R Before A2105
1052002-173A Before A2105 1052003-219U Before A2105 1052009-220D Before A2105
1052002-173C Before A2105 1052003-221U Before A2105 1052009-221D Before A2105
1052002-181A Before A2105 1052003-222U Before A2105 1052009-222D Before A2105
1052002-182A Before A2105 1052003-223U Before A2105 1052009-230A Before A2105
1052002-184C Before A2105 1052003-225U Before A2105 1052009-260A Before A2105
1052002-185C Before A2105 1052003-237U Before A2105 1052009-263A Before A2105
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 3 of 33

### Page 5

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE
1052009-264A Before A2105 1052009-445A Before A2105 1052010-377A Before A2105
1052009-266A Before A2105 1052009-447A Before A2105 1052010-378A Before A2105
1052009-267A Before A2105 1052009-449A Before A2105 1052010-379A Before A2105
1052009-274A Before A2105 1052009-450A Before A2105 1052010-383A Before A2105
1052009-275A Before A2105 1052009-452A Before A2105 1052010-396A Before A2105
1052009-289A Before A2105 1052009-453A Before A2105 1052010-400A Before A2105
1052009-291A Before A2105 1052009-454A Before A2105 1052010-404A Before A2105
1052009-296A Before A2105 1052009-455A Before A2105 1052010-413A Before A2105
1052009-297A Before A2105 1052009-456A Before A2105 1052010-415A Before A2105
1052009-300A Before A2105 1052010-082A Before A2105 1052010-416A Before A2105
1052009-306A Before A2105 1052010-090A Before A2105 1052010-419A Before A2105
1052009-315A Before A2105 1052010-093D Before A2105 1052010-433A Before A2105
1052009-321A Before A2105 1052010-100A Before A2105 1052010-437A Before A2105
1052009-324A Before A2105 1052010-101D Before A2105 1052010-439A Before A2105
1052009-325A Before A2105 1052010-103A Before A2105 1052010-440A Before A2105
1052009-326D Before A2105 1052010-127A Before A2105 1052010-443A Before A2105
1052009-328A Before A2105 1052010-130A Before A2105 1052010-444A Before A2105
1052009-328D Before A2105 1052010-145A Before A2105 1052010-448A Before A2105
1052009-329A Before A2105 1052010-149A Before A2105 1052010-453A Before A2105
1052009-331D Before A2105 1052010-176A Before A2105 1072004-134U Before A2105
1052009-333D Before A2105 1052010-186A Before A2105 1072004-137U Before A2105
1052009-334D Before A2105 1052010-189A Before A2105 1072004-144U Before A2105
1052009-335D Before A2105 1052010-197A Before A2105 1072004-150U Before A2105
1052009-336A Before A2105 1052010-213A Before A2105 1072004-171U Before A2105
1052009-336D Before A2105 1052010-216A Before A2105 1072004-188U Before A2105
1052009-337A Before A2105 1052010-216C Before A2105 1072004-198U Before A2105
1052009-343A Before A2105 1052010-221A Before A2105 1072004-200A95 Before A2105
1052009-348U Before A2105 1052010-228A Before A2105 1072004-200U95 Before A2105
1052009-353A Before A2105 1052010-233A Before A2105 1072004-205U Before A2105
1052009-356A Before A2105 1052010-237C Before A2105 1072004-207A Before A2105
1052009-356U Before A2105 1052010-262A Before A2105 1072004-210A Before A2105
1052009-357A Before A2105 1052010-265A Before A2105 1072004-211U Before A2105
1052009-362A Before A2105 1052010-267A Before A2105 1072004-215U Before A2105
1052009-363A Before A2105 1052010-283A Before A2105 1072004-226U Before A2105
1052009-365A Before A2105 1052010-286A Before A2105 1072004-232U Before A2105
1052009-366A Before A2105 1052010-290A Before A2105 1072004-237U Before A2105
1052009-369A Before A2105 1052010-291A Before A2105 1072004-241U Before A2105
1052009-373A Before A2105 1052010-298A Before A2105 1072004-255U Before A2105
1052009-375A Before A2105 1052010-299A Before A2105 1072004-262U Before A2105
1052009-377A Before A2105 1052010-303A Before A2105 1072004-266U Before A2105
1052009-382A Before A2105 1052010-309A Before A2105 1072004-275U Before A2105
1052009-383A Before A2105 1052010-314A Before A2105 1072004-305U Before A2105
1052009-386A Before A2105 1052010-315A Before A2105 1072004-307A Before A2105
1052009-399A Before A2105 1052010-318A Before A2105 1072004-307U Before A2105
1052009-403A Before A2105 1052010-322A Before A2105 1072004-312A Before A2105
1052009-404A Before A2105 1052010-333A Before A2105 1072004-312U Before A2105
1052009-406A Before A2105 1052010-347A Before A2105 1072004-315A Before A2105
1052009-407A Before A2105 1052010-354A Before A2105 1072004-319U Before A2105
1052009-409A Before A2105 1052010-357A Before A2105 1072004-325U Before A2105
1052009-412A Before A2105 1052010-361A Before A2105 1072004-330U Before A2105
1052009-415A Before A2105 1052010-364A Before A2105 1072004-349U Before A2105
1052009-431A Before A2105 1052010-368A Before A2105 1072004-350U Before A2105
1052009-433A Before A2105 1052010-371A Before A2105 1072004-358U Before A2105
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 4 of 33

### Page 6

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE
1072004-360U Before A2105 35554-2-310 Before A2105 35599-2-255 Before A2105
1072004-373A Before A2105 35554-3-400 Before A2105 35600-2-255 Before A2105
1072004-373U Before A2105 35555-2-255 Before A2105 35602-2-255 Before A2105
1074001-052C95 Before A2105 35556-4-310 Before A2105 35602-2-310 Before A2105
35510-3-400 Before A2105 35560-2-310 Before A2105 35602-4-310 Before A2105
35515-3-255 Before A2105 35560-2-575 Before A2105 35603-2-255 Before A2105
35518-2-310 Before A2105 35562-2-255 Before A2105 35607-2-310 Before A2105
35518-3-255 Before A2105 35562-4-255 Before A2105 35608-2-765 Before A2105
35518-3-310 Before A2105 35563-2-255 Before A2105 35608-2-900 Before A2105
35518-4-310 Before A2105 35563-2-310 Before A2105 35609-4-255 Before A2105
35520-2-765 Before A2105 35564-2-255 Before A2105 35610-2-765 Before A2105
35520-4-255 Before A2105 35565-2-255 Before A2105 35612-2-255 Before A2105
35521-4-310 Before A2105 35566-2-575 Before A2105 35612-4-310 Before A2105
35523-4-255 Before A2105 35567-0-310 Before A2105 35612-4-400 Before A2105
35524-2-255 Before A2105 35567-2-255 Before A2105 35615-2-310 Before A2105
35525-4-255 Before A2105 35567-2-310 Before A2105 35615-2-400 Before A2105
35526-2-255 Before A2105 35567-2-575 Before A2105 35615-4-255 Before A2105
35528-4-310 Before A2105 35569-0-310 Before A2105 35618-2-255 Before A2105
35529-2-255 Before A2105 35569-4-310 Before A2105 35618-4-310 Before A2105
35530-2-255 Before A2105 35570-2-255 Before A2105 35619-4-254 Before A2105
35530-2-310 Before A2105 35571-2-255 Before A2105 35619-4-255 Before A2105
35531-2-255 Before A2105 35572-0-255 Before A2105 35620-2-255 Before A2105
35532-4-255 Before A2105 35572-2-400 Before A2105 35620-2-400 Before A2105
35533-3-255 Before A2105 35573-2-310 Before A2105 35620-2-575 Before A2105
35533-4-255 Before A2105 35574-2-255 Before A2105 35620-3-575 Before A2105
35533-4-310 Before A2105 35574-2-310 Before A2105 35622-4-255 Before A2105
35534-2-255 Before A2105 35576-2-310 Before A2105 35622-4-310 Before A2105
35536-2-400 Before A2105 35578-2-255 Before A2105 35624-37-255 Before A2105
35537-2-255 Before A2105 35579-4-255 Before A2105 35624-4-255 Before A2105
35537-4-255 Before A2105 35580-2-255 Before A2105 35628-2-400 Before A2105
35537-4-310 Before A2105 35581-2-255 Before A2105 35631-4-255 Before A2105
35538-2-765 Before A2105 35581-2-400 Before A2105 35632-2-310 Before A2105
35539-2-255 Before A2105 35582-2-255 Before A2105 35632-4-255 Before A2105
35540-2-255 Before A2105 35583-2-255 Before A2105 35633-0-310 Before A2105
35540-2-310 Before A2105 35584-2-180 Before A2105 35634-4-255 Before A2105
35540-2-765 Before A2105 35584-2-255 Before A2105 35634-4-310 Before A2105
35541-0-310 Before A2105 35584-4-255 Before A2105 35635-4-255 Before A2105
35541-3-255 Before A2105 35584-4-310 Before A2105 35636-2-310 Before A2105
35542-4-310 Before A2105 35585-2-255 Before A2105 35639-2-255 Before A2105
35544-2-255 Before A2105 35587-2-255 Before A2105 35639-2-575 Before A2105
35544-3-255 Before A2105 35590-2-255 Before A2105 35640-4-310 Before A2105
35544-3-310 Before A2105 35591-2-255 Before A2105 35640-4-400 Before A2105
35545-2-255 Before A2105 35592-2-255 Before A2105 35644-2-575 Before A2105
35546-2-255 Before A2105 35592-3-255 Before A2105 35645-2-255 Before A2105
35547-2-255 Before A2105 35592-3-310 Before A2105 35646-4-255 Before A2105
35548-2-310 Before A2105 35593-3-255 Before A2105 35648-2-255 Before A2105
35548-4-255 Before A2105 35594-2-255 Before A2105 35649-4-255 Before A2105
35549-2-255 Before A2105 35594-4-400 Before A2105 35650-2-255 Before A2105
35550-2-310 Before A2105 35595-2-575 Before A2105 35651-2-255 Before A2105
35550-4-255 Before A2105 35596-2-255 Before A2105 35652-4-255 Before A2105
35552-2-310 Before A2105 35596-2-765 Before A2105 35655-2-310 Before A2105
35552-3-255 Before A2105 35596-4-255 Before A2105 35656-0-310 Before A2105
35553-3-255 Before A2105 35598-2-400 Before A2105 35656-2-255 Before A2105
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 5 of 33

### Page 7

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE PART NUMBER APPLICABLE TO DATE CODE
35659-2-255 Before A2105 35679-2-255 Before A2105 35777-200-255 Before A2105
35660-2-255 Before A2105 35680-0-255 Before A2105 35778-200-255 Before A2105
35660-2-310 Before A2105 35680-2-255 Before A2105 35780-200-255 Before A2105
35664-4-400 Before A2105 35732-200-400 Before A2105 35781-200-255 Before A2105
35664-4-575 Before A2105 35733-211-400 Before A2105 35791-400-400 Before A2105
35666-3-310 Before A2105 35737-400-400 Before A2105 35795-200-255 Before A2105
35668-0-900 Before A2105 35753-211-400 Before A2105 35807-400-400 Before A2105
35668-2-310 Before A2105 35755-200-400 Before A2105 35812-200-255 Before A2105
35669-2-255 Before A2105 35760-411-575 Before A2105 35871-400-400 Before A2105
35676-2-255 Before A2105 35767-211-400 Before A2105 35874-411-400 Before A2105
35678-3-255 Before A2105 35774-200-255 Before A2105
NOTE: Numeric Date Code: AYYWW (YY 2-digit year, WW 2-digit Week) Example A2105
(Date of Manufacture 5th week of 2021).
NOTE: For CRJ 200/700/900/1000 refer to service bulletin CFD-26-5.
B. Concurrent Requirement
Not applicable.
C. Reason
(1) Description of Existing Condition
(a) CFDs produced between November 24, 2004 (A0448) and January 31, 2021 (A2105) 
may not properly detect thermal bleed leak events. This specific failure mode is not
detectable by on-board diagnostics.
(2) Extent Condition Encountered
(a) Any CFD Part Numbers listed in Section 1.A. may be affected.
(3) Expected Benefits of Modification
(a) Verification that CFD’s will operate normally.
(4) Safety Intent of Corrective Action
(a) Identify inoperable units by testing for functionality.
(b) Remove inoperable units from the field.
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 6 of 33

### Page 8

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
(5) Regulatory Action
(a) To be determined by the governing civil aviation authority.
D. Description
Bench Test CFD’s for proper operation. Failed units will be replaced Free Of Charge (FOC) 
by Kidde Aerospace and Defense.
E. Compliance
Optional - Service Bulletin for convenience or option.
Recommended - Service Bulletin to introduce improvements.
Highly Recommended - Service Bulletin recommended to be accomplished to prevent 
significant operational disruptions.
X Mandatory - Service Bulletin must be accomplished.
F. Approval
The approved design of the CFD part numbers listed in Section 1.A is in compliance with the 
requirements of TSO-C11e. This SB allows you to determine if the suspect parts conform to 
the approved design.
G. Manpower
The total estimated time to accomplish the work in this service bulletin is 0.5 man hours per 
unit.
TASK ESTIMATED HOURS
Preparation 0.2
Installation 0.0
Testing 0.3
Total 0.5
H. Weight and Balance
No change.
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 7 of 33

### Page 9

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
I. Electrical Load Data
No change.
J. Software Accomplishment Summary
None.
K. References
(1) Abbreviated Component Maintenance Manual (ACMM) for 1052002-XXXX, 36-22-22 
(2) ACMM for 1052003-XXXX, 36-22-32
(3) ACMM for 1052009-XXXX, 36-22-33
(4) ACMM for 1052010-XXXX, 36-22-44
(5) ACMM for 1072004-XXXX, 36-22-21
(6) ACMM for 04-31102-XXXX, 26-14-47
(7) ACMM for 04-90011-XXXX, 26-14-34
(8) ACMM for 04-90025-XXXX, 26-12-05
(9) ACMM for 04-90026-XXXX, 26-12-06
(10) ACMM for 04-90028-XXXX, 36-22-07
(11) ACMM for 04-90030-XXXX, 36-22-15
(12) ACMM for 04-90031-XXXX, 36-22-08
(13) ACMM for 04-90032-XXXX, 36-22-09
(14) ACMM for 04-90033-XXXX, 36-22-13
(15) ACMM for 04-90034-XXXX, 36-22-14
(16) ACMM for 355XX-X-XXX, 26-14-12
(17) ACMM for 356XX-X-XXX, 26-10-09
(18) ACMM for 357XX-XXX, 358XX-XXX, 26-14-33
L. Other Publications Affected
None.
M. Interchangeability or Intermixability of Parts
Fully Interchangeable and intermixable
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 8 of 33

### Page 10

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
2. MATERIAL INFORMATION
A. Cost and Availability
Tooling Kit part number 173948 available.
NOTE: Tooling Kit 173948 contains items from tables in Section 2.C.(3) & C.(4). 
NOTE: Order if test equipment is not available.
NOTE: The current charge for Collins to perform this service bulletin is $794.60 United States
Dollars (USD) and may be subject to future price adjustments. Pricing is only valid through 
December 31, 2022.
B. Industry Support Information
(1) The modification materials in this service bulletin may be obtained from:
No modification materials required for this Service Bulletin
(2) The tooling kit in this service bulletin may be obtained from:
Rockwell Collins
Rental Exchange
400 Collins Road NE
Cedar Rapids, IA 52498-0001
US Phone: 1.800.713.7693
International Phone: 1.319.295.4361
Email: Collinsdispatchprograms@rockwellcollins.com
Include the following:
Email Subject: CFD NOE Kit
Provide FOC PO
Power Requirements: 110V or 220V
NOTE: Order if test equipment is not available.
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 9 of 33

### Page 11

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
(3) Warranty
For units in and out of warranty, Collins Aerospace will perform this service bulletin at no 
charge for the materials and labor or reimburse the cost of this service bulletin.
NOTE: Warranty claims will be accepted through December 31, 2026. 
(4) Instructions for Warranty Claims can be found at:
https://portal.rockwellcollins.com/web/support-self-service/warranty
(5) Operators can also forward claims for labor reimbursement to the e-mail:
kiddewarranty@collins.com
C. Material Necessary for Each Component
(1) Materials Purchased
None.
(2) Materials Supplied by Customer
PART NUMBER KEY WORD DESCRIPTION QUANTITY SPECIAL INSTRUCTION/DISPOSITION
Commercially Available Marking Material Customer Preference As Required(AR) Locally Sourced
(3) Materials Purchased for Testing Procedure
PART NUMBER KEY WORD DESCRIPTION QUANTITY SPECIAL INSTRUCTION/DISPOSITION
Kit 173948 Contains the items below as well as items in the Table from Section 2.C.(4)
1146006-0254-00
CFD
Connecting
Cable
100in, Gold, 
Pin Connector 2 N/A
1148006-0254-00
CFD
Connecting
Cable
100in, Gold, 
Socket Connector 2 N/A
476232 CFD Shell and
Insert Assy Gold 20
Contact Socket -Capable 
receiving 0.06 inch (1.52
mm) diameter contact pin
349457 CFD Contact
Pin Gold 20 Gold Plated 0.06 inch (1.52mm) diameter
(4) Materials Supplied by Customer for Testing Procedure
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 10 of 33

### Page 12

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
PART NUMBER KEY WORD DESCRIPTION QUANTITY RANGE TOLERANCE
BK 879B or
Equivalent LCR Meter Electronic Test Equipment 1
1 kHz test frequency 
0.6-1.0 Vrms test level 
0 VDC
0-40 kΩ Z impedance
32-104°F (0-40 °C) 
operate temp
±5%
Not applicable
±0.02 VDC
±5%
Not applicable
Steinel HG2320E1 or 
Equivalent Heat Gun Heating Gun 1 32-662°F (0-350 °C) (at nozzle) ±10 °F (±5 °C)
Steinel 07051 or 
Equivalent Heat Gun Shield Heat Shield 1 N/A N/A
HH501BJK or Fluke 
289 or Equivalent
Digital Multimeter 
(DMM)/Digital 
Temperature 
Meter (DTM)
Measures
Temperature 1
Type K input 32- 1100°
F (0-594°C)
32-104°F (0-40 °C) 
operate temp
±4°F (±2.2°C) or 0.75% 
(whichever is greater)
Not applicable
KMQSS-062U-12 or 
Equivalent Thermocouple MeasuresTemperature 1 Type K input 32- 1100°F (0-594°C) or greater ±4°F (±2.2°C) or 0.75% (whichever is greater)
4TM11 or Equivalent Stopwatch StopwatchTime 1 2 minutes (min) 1 second resolution (±5 secs over range)
1 For G salt sensing element only an 842°F (450 °C) heat source is required
D. Re-Identified Parts/Existing Parts Accountability
None Required.
E. Special Tools
None
3. ACCOMPLISHMENT INSTRUCTIONS
NOTE: Some steps in the accomplishment instructions are identified as Required for Compliance 
(RC). If this service bulletin is mandated by an airworthiness directive (AD), the steps identified 
as RC must be done to comply with the AD. Steps not identified with RC are recommended and 
may be deviated from; done as a part of other actions; or done with accepted methods different 
from those given in SB if the RC steps can be done and the airplane returned to a serviceable 
condition.
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 11 of 33

### Page 13

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
A. Modification Procedure
(1) No part modifications that impact operation are being made. Go to Section 3.B.
B. Test Procedures
(1) RC - Test Environment
Testing shall be performed at a room temperature between 55°F (12.8°C) and 85°F (29.4°
C), and relative humidity not exceeding 90%. The test area must be free from flammable 
vapors. The work surface used for bench top testing must be made from non- flammable 
and non-conductive materials.
WARNING: Hot air tool can produce up to 1300°F (795°C) of flameless heat at the nozzle. 
Do not direct airstream at clothing, hair, or other body parts. If the hot air is set above 392°
F (200°C), ensure the surroundings are free of fuel vapors and other ignition sources.
WARNING: Do not use near flammable liquids or in an explosive environment (fumes, 
gases, or dust). Remove materials or debris that may become ignited from work area.
WARNING: Always hold tool by plastic enclosure. The metal nozzle requires 
approximately 20 minutes to cool to where it can be touched. Do not touch nozzle or 
accessory tips until cool.
WARNING: Do not store tool until nozzle has cooled to room temperature. Place tool in a 
clear area away from combustible materials while cooling.
WARNING: Use shield materials around the heated area to prevent damage or fire.
CAUTION: Do not cut off airflow by placing nozzle too close to work piece. Keep intake 
vents clean and clear of obstructions.
WARNING: Do not leave tool unattended while running or cooling down. Otherwise risk of
fire.
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 12 of 33

### Page 14

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
CAUTION: Place tool on a level surface when tool is not handheld. Place cord in a position 
that won’t cause tipping.
NOTE: Keep a fully charged fire extinguisher nearby.
(2) RC - Sensing Elements Heating Procedure
The following figures show how to use the heat gun. A heat protection shield must be used 
and attached to the end of the heat gun outlet. A heat protection shield (Steinel P/N 07051) 
is normally supplied in the referenced kit. If not available, the following dimensions can be 
followed to produce an acceptable heat protection shield. The heat protection shield shall 
be 1.4±0.2 inch (~3.56 cm ±0.5 cm) in width and rolled in a half circle with a radius of 
approximately 0.75 inches (1.91 cm) for optimum testing. The end of the half circle shall 
be 1.25-1.5 inches (~3.18 to 3.81 cm) away from the heat gun outlet as shown in Figure 1 
and Figure 2.
Figure 1: Heat Protection Shield Side View
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 13 of 33

### Page 15 (OCR)

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION - CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
OFF-AXIS
THERMOCOUPLE
LOCATION
TC TIP PLACED 0.33 INCH (0.85 cm) FROM CENTERUNE
HEAT GUN OUTLET
1.2 TO 1.6 INCH  HEAT PROTECTION  AIRFLOW
(3.06 TO 4.06 cm)  SHIELD
SENSING
ELEMENT  TC TIP ON CENTERLINE OF HEAT FLANGE
CENTER
THERMOCOUPLE
LOCATION  -1.00 to 1.25 INCH-
(2.54 TO 3.18 cm)
Figure 2: Heat gun with heat protection shield top down view
If a curved heat protection shield is not available place a flat heat protection shield (i.e.
aluminum plate) behind the sensing element being heated and hold the heat gun
1.00 -1.25 inch (2.54 to 3.18 cm) from the sensing element as shown in Figure 3.
SENSING
HEAT PROTECTION  ELEMENT
SHIELD
HEAT GUN OUT LET
(3.06 TO 4.06 cm)  1.2 TO 1.6 INCH  -1.00 to 1.25 INCH  AIRFLOW
(2.54 TO 3.18 cm)
0.25 TO 0.5 INCH
(0.64 TO 1.27 cm)
Figure 3: Heat gun using heat protection shield side view
(3) RC - Test Equipment setup
(a) Heat Gun Temperature Verification at sensing element position:
February 28/22  CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 14 of 33

### Page 16

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
NOTE: To ensure that the Heat Gun Temperature is consistent during all testing, this 
verification procedure shall be performed prior to testing the first sensing element of 
each alarm set point and repeated after every four hours of testing or when the sensing 
element set point changes or when the ambient conditions in the test location change 
but not less than once per shift.
1) Install the heat protection shield on the heat gun as shown in Figure 1.
2) Connect the thermocouple to the Digital Multimeter (DMM) or Digital Temperature
Meter (DTM) and set the DMM or DTM to measure temperature.
3) Turn on the heat gun and set airflow rate to maximum on the heat gun if the setting
is available.
4) Place the thermocouple at the center of the heat protection shield, not touching the 
shield, at the approximate location the sensing element will be placed as shown in
Figure 1 and Figure 2.
5) Set the heat gun temperature so that the thermocouple reads the Thermocouple
Test Temperature value specified in Table 1 for the correct Salt Type Letter.
NOTE: It is recommended that the Heat Gun setting temperature be initially set high 
enough such to achieve a Thermocouple Test Temperature that uses approximately 
½ the allowable temperature tolerance defined in Table 1.
NOTE: For Heat Guns with a digital display, the Heat Gun display temperature will 
typically be higher than the temperature at the thermocouple.
NOTE: During Heat Gun Temperature Settings calibration to achieve the 
Thermocouple Test Temperature, the thermocouple temperature will slightly vary up 
and down according to the thermal regulation of the Heat Gun. The temperature 
values recorded should be the average of the observed results.
6) Verify and record that the center thermocouple temperature value is within the
Thermocouple Test Temperature value tolerance specified in Table 1.
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 15 of 33

### Page 17

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
7) Move and place the thermocouple approximately 0.33 inch (0.85 cm) from the 
centerline of the heat protection shield left or right at the approximate location the
sensing element will be placed as shown in Figure 1 and Figure 2.
NOTE: If measuring the 2nd location right of centerline, route thermocouple from the 
right. If measuring the 2nd location left of centerline, route thermocouple from the left.
NOTE: The Heat Gun 2nd or off-axis location may be below the lower limit in the 
Table 1 as the temperature may reduce near the edges left or right of center test 
position.
8) Record the second or off-axis thermocouple value.
9) Calculate the two (2) point average temperature of the center point and second or
off-axis thermocouple readings.
EXAMPLE
Salt Type Letter
Center Thermocouple
Temperature (T center)
2nd Location (off axis)
Thermocouple 
Temperature (T 2nd)
2 pt Average
Thermocouple Test
Temperature
A 290 °F / 143 °C 260 °F / 127 °C 275 °F / 135 °C
FORMULA: 2pt Average Thermocouple Test Temperature
= (T center + T 2nd)/2
= (290 °F + 260 °F)/2
= 275 °F
10) If the above 2 Point (pt) average Thermocouple Test Temperature value is not 
within the tolerance allowed in Table 1 using a Center and Left off axis position or 
Center and Right off axis position, attempt steps 4) through 9) trying the opposite 
side of the tested Center and Left or Right off axis position until the 2 Point (pt) 
average Thermocouple Test Temperature value is within the tolerance limits. This 
will mitigate some heat gun variability.  If the testing is not successful, replace the
heat gun with one with a more uniform output.
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 16 of 33

### Page 18

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
NOTE: It is recommended this value be near or approximately at the mid-point of 
the temperature range defined by the tolerance in Table 1.
11) Record the two (2) point average Thermocouple Test Temperature verification 
temperature under the pre-test remarks Data Sheet in Table 2 (Refer Appendix A)
for reference only.
(b) For Center Wire Resistance (CWR) Measurements
NOTE: CWR Measurements must be taken with an LCR meter and not a DMM. There 
are Sensing Element DC offset voltage restrictions that are required to be maintained 
as well as electrical connection constraints to prevent Sensing Element polarization 
damage risk.
o The LCR meter shall be configured as follows:
§ Measurement mode:  Resistance (R)
§ Range:  100 Ω or 200 Ω as applicable
o The LCR meter shall be capable of meeting the following requirements:
§ Frequency:  1 kHz
§ Bias:  0.6-1.0 Vrms, 0 Vdc offset
NOTE: These settings must be set at the meter if configurable or it must be confirmed 
that the meter is capable of these settings if not configurable.
(c) For Salt Core Impedance (SCI) Measurements
o The LCR meter shall be configured as follows:
§ Measurement mode:   Impedance (Z)
§ Heated range:  10 Ω or 10000 Ω as applicable
§ Room Temperature Impedance range:  10000 Ω or 10MΩ as applicable 
o The LCR meter shall be capable of meeting the following requirements:
§ Frequency:  1 kHz
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 17 of 33

### Page 19

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
§ Bias:  0.6-1.0 Vrms, 0 Vdc offset
CAUTION: When you do the test, do not use a meter that applies dc voltage. Do not 
use insulation resistance "megger" testers or dielectric voltage "hypot" testers. These 
will damage the sensing element.
NOTE: These settings must be set at the meter, if configurable or it must be confirmed 
that the meter is capable of these settings if not configurable.
(4) RC - Bench Top Thermal Test Procedure
(a) Test locations
1) Refer to Figure 4 below for test locations and test sections:
Figure 4: Test Locations for Compartment Overheat
2) For sensing elements longer than 30 inch (76.2 cm) it shall be tested in three (3) 
locations. Testing shall NOT be performed within 1 inch (2.54 cm) of the
connectors:
a) The 1st location shall be from 2-14 inches (5-35 cm) from the beginning of the 
sensing element and as close to the end as limits allow.  Each location will 
consist of 3 test points with a 3-4 inch (7.62 to 10.16 cm) center to center 
spacing between each test point. If the “Heated Impedance” Z value is below 
the Zeq(limit) for test point 1, test point 2, or test point 3, no additional test 
points within this test location are required and can be entered directly on the 
data sheet as the final Zeq(Calc). If the “Heated Impedance” Z value is at or 
above the Zeq(limit) for all 3 test points, the Zeq(Calc) will have to be
calculated.
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b) The 2nd location shall be a location between 33% and 67% of the length of the 
sensing element AND at least 10 inches (25 cm) from the 1st and 3rd test 
locations for sensing elements longer than 60 inches (152.4 cm). Each location 
will consist of 3 test points with a 3-4 inch (7.62 to 10.16 cm) center to center 
spacing between each test point. If the “Heated Impedance” Z value is below 
the Zeq(limit) for test point 1, test point 2, or test point 3, no additional test 
points within this test location are required and can be entered directly on the 
data sheet as the final Zeq(Calc). If the “Heated Impedance” Z value is at or 
above the Zeq(limit) for all 3 test points, the Zeq(Calc) will have to be
calculated.
c) The 3rd location shall be from 2-14 inches (5-35 cm) from the opposite end of 
the sensing element and as close to the end as limits allow.  Each location will 
consist of 3 test points with a 3-4 inch (7.62 to 10.16 cm) center to center 
spacing between each test point. If the “Heated Impedance” Z value is below 
the Zeq(limit) for test point 1, test point 2, or test point 3, no additional test 
points within this test location are required and can be entered directly on the 
data sheet as the final Zeq(Calc). If the “Heated Impedance” Z value is at or 
above the Zeq(limit) for all 3 test points, the Zeq(Calc) will have to be
calculated.
3) If the sensing element is between 14 - 30 inches (35 - 76.2 cm) long it shall be 
tested in two (2) locations. Testing shall NOT be performed within 1 inch (2.54 cm)
of the connectors:
a) The 1st location shall be from 2-14 inches (5-35 cm) from the beginning of the 
sensing element and as close to the end as limits allow. Each location will 
consist of 3 test points with a 3-4 inch (7.62 to 10.16 cm) center to center 
spacing between each test point. If the “Heated Impedance” Z value is below 
the Zeq(limit) for test point 1, test point 2, or test point 3, no additional test 
points within this test location are required and can be entered directly on the 
data sheet as the final Zeq(Calc). If the “Heated Impedance” Z value is at or 
above the Zeq(limit) for all 3 test points, the Zeq(Calc) will have to be
calculated.
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b) The 2nd location shall be from 2-14 inches (5-35 cm) from the end of the sensing 
element and as close to the end as limits allow. Each location will consist of 3 
test points with a 3-4 inch (7.62 to 10.16 cm) center to center spacing between 
each test point. If the “Heated Impedance” Z value is below the Zeq(limit) for 
test point 1, test point 2, or test point 3, no additional test points within this test 
location are required and can be entered directly on the data sheet as the final
Zeq(Calc). If the “Heated Impedance” Z value is at or above the Zeq(limit) for
all 3 test points, the Zeq(Calc) will have to be calculated.
4) Preformed and non-preformed sensing elements less than 14 inches (35 cm) shall 
be tested in one (1) location and at (1) test point furthermost distance from the 
connectors.  Testing shall NOT be performed within 1 inch (2.54 cm) of the 
connectors.  Avoid aiming the heat gun at any grommets used to attach the sensing 
element if installed on a bracket.  In some instances, the heat gun flange must be 
removed in order to effectively execute the testing of the preformed sensing 
elements.  The preformed sensing elements shall be tested to the thermocouple
test temperature identified in Table 1 plus 65°F (36°C).
a) The 1st and only (middle) location shall be in the middle area farthest from the 
beginning and end of the sensing element that has a width of approximately 1.5
to 2.0 inches (3.81 to 5.08 cm).
(b) Test article preparations
1) Remove the sensing element from packing material ensuring that the packing 
material is stored in a location where it will be shielded from the output of the heat
gun.
2)  Uncoil the non-preformed sensing element to ensure access to the necessary 
start, middle, and end locations required for testing. Minimize bending to ensure 
easier re-coiling and return to packaging. Ensure sensing elements are left straight 
and not bent for a minimum of 1 inch (2.54 cm) from rear hex nuts of the sensing
element connectors.
CAUTION: Do not uncoil/straighten preformed sensing elements. They cannot be
easily re-formed without a precision fixture.
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3)  Mark the test points at each test location using a permanent ink marker. Refer to
Section 3.B.(4).(a) Test Locations for instructions on test locations.
NOTE: Permanent Marker will not affect element operation. It is not necessary to 
remove the markings after testing is complete.
4)  Select test cable (P/N 1146006-0254-00 or 1148006-0254-00), test contact pin (P/
N 349457), or test contact pin (P/N 349457) and shell & insert assembly (P/N 476232), 
which best mate with the sensing element under test. For sensing elements which 
are terminated with Lugs, the test lead can be clipped to the lug
for the center wire connection and the sensing element sheath for the common
connection.
CAUTION: Use a connection cable or install a test pin in the socket connector to
prevent damage to the sensing element connectors.
5)  Turn on the LCR meter. If the meter is configurable, set the LCR meter to a test 
frequency of 1 kHz, DC bias to 0 VDC, signal amplitude to approximately 0.8 ±0.2 
Vrms, and measurement mode of “Z”. If the meter is not configurable, using the
meter specification sheet, ensure theses parameters are met on the LCR meter.
6)  Connect the LCR meter for the appropriate measurement type as described below:
For CWR measurements:
a) Connect the center wire of the connecting cable or contact pin on one
end of the sensing element to one terminal on the LCR meter.
b) Connect the center wire of the connecting cable or contact pin on the
other end of the sensing element to the other terminal on the LCR meter.
NOTE:  It is expected that the connecting cable impedance is less than 0.25 
Ohms. It may be necessary to subtract the connecting cable impedance if the 
tolerances in Section 2.C.(4) Table are not met.
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For SCI measurements:
a) Connect the center wire of the connecting cable or contact pin to the
plus or positive terminal on the LCR meter
b) Connect the negative terminal on the LCR meter to the shield of the
connecting cable or the sensing element tube near one connector (away 
from the area or end being heated)
CAUTION: When connecting the cable to the sensing element, support the 
cable back shell with one hand and the sensing element end with the other, 
then twist the nut until tight. Do not twist the sensing element or the mating test 
cable if used.
NOTE: If using a test cable, ensure that when the mating cable is connected 
from pin and/or socket connectors, that the mating cable is held so that it does 
not rotate while threading and connecting to the sensing element connector. An 
incremental threading and engagement pushing while holding the connector is 
required to ensure the mating cable is not twisting and damaging the core 
cables or mating pin contacts or shell and insert assemblies. Same for 
disconnecting except in reverse.
(c) Test Set Up
1) For CWR measurements:
a) Turn on the LCR meter.
b) Refer to the LCR meter operating manual to set the required measurement
test conditions. Typical example would be to set the measurement 
parameter by selecting or entering on the applicable meter buttons 
(example “L/C/R/Z”); setting the measurement frequency by selecting or 
entering on the applicable meter buttons (example “FREQ”); setting the 
measurement AC amplitude by selecting or entering on the applicable meter 
buttons (example “AC”); and setting the measurement DC bias to 0 by 
selecting or entering on the applicable meter buttons (example “DC”);
c) Set the LCR meter to Measurement parameter mode of “R”.
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d) Set the LCR meter measurement frequency to 1 kHz if configurable. If the
meter is not configurable, using the meter specification sheet, ensure these 
parameters are met on the LCR meter.
e) Set the LCR meter measurement AC amplitude to approximately 0.8 +/- 0.2
Vrms and DC bias or offset to 0 Vdc. If the meter is not configurable, using 
the meter specification sheet, ensure the LCR meter parameters in Section 
2.C.(4) Table are met.
f) Set the measurement range as applicable (100Ω or 200Ω) if applicable.
g) Ensure the LCR meter is connected to the sensing element start and the
sensing element End.
NOTE:  It is expected that the connecting cable impedance is less than 0.25 Ohms. 
It may be necessary to subtract the connecting cable impedance if the tolerances 
in Section 2.C.(4) Table are not met.
2) For SCI measurements:
a) If the meter is configurable, set the LCR meter to a test frequency of 1 kHz,
ensure or set DC bias to 0Vdc, AC signal amplitude to approximately 0.8 
+/- 0.2 Vrms, and measurement mode of “Z”. If the meter is not configurable, 
using the meter specification sheet, ensure these parameters are met on 
the LCR meter.
b) Ensure the LCR meter is connected to the sensing element start/end and
the sensing element ground (sensing element tube).
CAUTION: When you do the test, do not use a meter that applies dc voltage. Do 
not use insulation resistance "megger" testers or dielectric voltage "hypot" testers. 
These will damage the sensing element.
(d) Test Procedure
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1) Enter the top section information (P/N, S/N, Date Code, Ambient Temperature, Pre 
Test Remarks, etc.) and record the results on Data Sheet in Table 2 (Refer
Appendix A).
Table 1: Heat Gun Temperature Settings
Salt
Type
Letter
Salt Temp Thermocouple TestTemperature* Family PN Zeq(Snsr)ohms
A 255 °F / 124 °C 275 (-0,+30) °F / 135 (-0,+17) °C
1052003 136
1052009 136
1052010 97
1072004 148
04-31102 97
04-90028 148
04-90030 97
ALL OTHERS 127
C 310 °F / 154 °C 332 (-0,+30) °F / 167 (-0,+17) °C
1074001 81
04-90022 97
ALL OTHERS 68
D 400 °F / 204 °C 427 -0,+30) °F / 219 (-0,+17) °C
1052009 136
ALL OTHERS 97
M 180 °F / 82 °C 196 -0,+30) °F / 91 (-0,+17) °C
1052003 136
ALL OTHERS 128
R 356 °F / 180 °C 381 (-0,+30) °F / 194 (-0,+17) °C ALL 81
U 210 °F / 99 °C 228 (-0,+30) °F / 109 (-0,+17) °C
1052003 136
1052009 136
1072004 148
ALL OTHERS 151
N 460 °F / 238 °C 491 (-0,+30) °F / 255 (-0,+17) °C
04-31102 56
ALL OTHERS 113
F 575 °F / 302 °C 612 (-0,+30) °F / 322 (-0,+17) °C ALL 31
G 765 °F / 408 °C 812 (-0,+30) °F / 433 (-0,+17) °C ALL 31
*For preformed sensing elements 14” (35 cm) or less, the Thermocouple Test 
Temperature will be the value stated in Table 1 plus 65 °F (36 °C)
NOTE: The Salt Type is designated by the P/N in one of two ways:
The letter in the P/N (i.e. 04-31102-026A is Salt Type “A”)
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The end dash number (i.e. 35560-2-575 is Salt Temp “F”)
WARNING: If the hot air is set above 392 °F (200 °C), ensure the surroundings are 
free of fuel vapors and other ignition sources.
2) Measure the Center Wire Resistance and log the value in the Data Sheet Table 2
(Refer Appendix A).
3) Turn on the heat gun and set and verify the temperature at the interval frequency 
per Section 3.B.(3) using the Thermocouple Temperature values specified in Table
1. Allow the heat gun to preheat for a minimum of 30 seconds (0.5 minutes) and
must reach proper stable test temperature. Ensure that the exhaust of the heat gun 
is directed in a safe direction. Refer to individual P/N top level drawings to 
determine salt type.
4) Measure and record the “Room Temperature Impedance” using the LCR meter and
SCI Measurement criteria. The value must be ≥ 10 kΩ and < 3MΩ. Log the value 
on the Data Sheet Table 2 (Refer Appendix A). Refer to Section 3.B.(4).(e).2) Post 
Test for values that are out of tolerance.
NOTE: If the “Room Temperature Impedance” is ≥ 3MΩ check LCR meter lead 
continuity by shorting leads together and then verify LCR meter to sensing element 
lead connections and retest if necessary.
5) Heat the 1st test point in the first test location for a minimum of 60 seconds (1 
minute) and no more than 120 seconds (2 minutes). Refer to Section 3.B.(4).(a)
Test Locations  for instructions on test locations.
NOTE: If the “Heated Impedance” is below the Zeq(limit) for five (5) or more 
seconds prior to 60 seconds, the full 60 seconds wait time is NOT required (can 
proceed to next test location).
NOTE: For optimum test execution it is best to measure the CWR value first, then 
calculate the Zeq(limit). Perform the individual heated test points and assess if they 
are below the Zeq(limit).  If not, continue heating additional local test points up to
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three (3) total before advancing to the next test location of the sensing element. 
Individual Z readings are not required to be ≤ Zeq(limit).  Individual Z readings must 
be >0.4Ω and < 3 MΩ (the upper room temperature impedance limit). Repeat the 
same testing method until all three (3) test locations of the sensing element are 
tested. Then go back and perform the Zeq(Calc) math calculations to assess pass/
fail.
6) Measure and record the “Heated Impedance” using the LCR meter and SCI 
Measurement criteria. Repeat Steps 5) to 7) for a total of three (3) times within this
test location area (3 readings) with a 3 to 4 inch (7.62 to 10.16 cm) spacing.
NOTE: If the “Heated Impedance” Z value is below the Zeq(limit) for test point 1, 
test point 2, or test point 3, no additional test points within this test location are 
required and can be entered directly on the data sheet as the final Zeq(Calc).
7) Record each value on the Data Sheet and then use the values to calculate the
Zeq(calc) value using the formula below:
Zeq(Calc) = 1 / {(1/Z1 + 1/Z2 + 1/Z3)}
The Zeq(calc) value shall be less than or equal to the Zeq(limit) value.  Zeq(limit) 
= Zeq(snsr) from Table 1 for the salt type sensing element + ½ * CWR measured 
value in ohms and greater than 0.4Ω.
EXAMPLE:  Target Limit = 127 Ω  CWR = 4 Ω
Zeq(Calc) < 127 + 4/2 Zeq(Calc) < 129
Z1 = 170 Ω Z2 = 400 Ω Z3 = 1200 Ω
Zeq(Calc) = 1 / {(1/170 + 1/400 + 1/1200)}
Zeq(Calc) = 108 Ω  Unit Passes
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NOTE: The calculation is derived to account for differences between this test 
procedure and the Acceptance Test Procedure (ATP).
8) Log the Zeq(limit) and Zeq(calc) value on the Data Sheet Table 2 (Refer Appendix
A).
NOTE: The Zeq(Calc) value may be calculated once all 3 test pints within a test 
location are complete. It is not required to calculate Zeq(Calc) before moving on 
from a single test location .
9) Remove the heat gun from sensing element and let it cool for three (3) minutes or 
until the “Room Temperature Impedance” is above the limit (see next step). Wipe
the sensing element with a damp cloth to restore it to room temperature.
a) If the sensing element does not result in a Zeq value less than or equal to the 
limit with the heat gun applied, then check the connections and repeat Steps 3) 
thru 7) and if necessary, change the test connection to the sensing element to
the end nearest the test location.
b) If the sensing element does not result in a Zeq value less than or equal to the 
limit with the heat gun applied upon retest, then refer to Section 3.B.(4).(e).2)
Post Test for values that are out of tolerance.
NOTE: If the “Room Temperature Impedance” increases above the limit for five (5) 
or more seconds prior to three (3) minutes with the damp cloth removed, the full 
three (3) minutes wait time is NOT required (can proceed to next test location).
10) Measure and record the “Room Temperature Impedance” using the LCR meter and 
SCI Measurement criteria. The value must be between 10 kΩ and 3MΩ. Log the 
value on the Data Sheet Table 2 (Refer Appendix A). Refer to Section 3.B.(4).(e).2)
Post Test for values that are out of tolerance.
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11) Heat the 1st test point in the second test location for a minimum of 60 seconds (1 
minute) and no more than 120 seconds (2 minutes). Refer to Section 3.B.(4).(a)
Test Locations for instructions on test locations.
NOTE: If the “Heated Impedance” is below the Zeq(limit) for five (5) or more 
seconds prior to 60 seconds, the full 60 seconds wait time is NOT required (can 
proceed to next test location).
NOTE: For optimum test execution it is best to measure the CWR value first, then 
calculate the Zeq(limit). Perform the individual heated test points and assess if they 
are below the Zeq(limit).  If not, continue heating additional local test points up to 
three (3) total before advancing to the next test location of the sensing element. 
Individual Z readings are not required to be ≤ Zeq(limit).  Individual Z readings must 
be >0.4Ω and < 3 MΩ (the upper room temperature impedance limit). Repeat the 
same testing method until all three (3) test locations of the sensing element are 
tested. Then go back and perform the Zeq(Calc) math calculations to assess pass/
fail.
12) Measure and record the “Heated Impedance” using the LCR meter and SCI 
Measurement criteria. Repeat Steps 11) thru 13) for a total of three (3) times within
this test location area (3 readings) with a 3 to 4 inch (7.62 to 10.16 cm) spacing.
NOTE: If the “Heated Impedance” Z value is below the Zeq(limit) for test point 1, 
test point 2, or test point 3, no additional test points within this test location are 
required and can be entered directly on the data sheet as the final Zeq(Calc).
13) Record each value on the data sheet and then use the values to calculate the
Zeq(calc) value using the formula below:
Zeq(Calc) = 1 / {(1/Z1 + 1/Z2 + 1/Z3)}
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The Zeq(calc) value shall be less than or equal to the Zeq(limit) value.  Zeq(limit) 
= Zeq(snsr) from Table 1 for the salt type sensing element + ½ * CWR measured 
value in Ohms and greater than 0.4Ω.
14) Log the Zeq(limit) and Zeq(calc) value on the Data Sheet Table 2 (Refer Appendix
A).
NOTE: The Zeq(Calc) limit may be calculated once all three (3) test points on a 
sensing element are complete.  It is not required to calculate Zeq(Calc) before 
moving on from a test location.
15) Remove the heat gun from sensing element and let it cool for at least 3 minutes. A
damp cloth can be used to restore sensing element to room temperature.
a) If the sensing element does not result in a Zeq value less than or equal to the 
limit with the heat gun applied, then check the connections and repeat Steps 
10) through 13) and if necessary, change the test connection to the sensing
element to the end nearest the test location.
b) If the sensing element does not result in a Zeq value less than or equal to the 
limit with the heat gun applied upon retest, then refer to Section 3.B.(4).(e).2)
Post Test for values that are out of tolerance.
NOTE: If the “Room Temperature Impedance” increases above the limit for five (5) 
or more seconds prior to three (3) minutes with the damp cloth removed, the full 
three (3) minutes wait time is NOT required (can proceed to next test location).
16) Measure and record the “Room Temperature Impedance” using the LCR meter and 
SCI Measurement criteria. The value must be ≥ 10 kΩ and < 3 MΩ. Log the value
on the Data Sheet Table 2 (Refer Appendix A). Refer to Section 3.B.(4).(e).2) Post
Test for values that are out of tolerance.
17) Heat the 1st test point in the third test location for a minimum of 60 seconds (1 
minute) and no more than 120 seconds (2 minutes). Refer to Section 3.B.(4).(a)
Test Locations for instructions on test locations.
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NOTE: If the “Heated Impedance” is below the Zeq limit for 5 or more seconds prior 
to 60 seconds, the full 60 seconds wait time is NOT required (can proceed to next 
test location).
NOTE: For optimum test execution it is best to measure the CWR value first, then 
calculate the Zeq(limit). Perform the individual heated test points and assess if they 
are below the Zeq(limit).  If not, continue heating additional local test points up to 
three (3) total before advancing to the next test location of the sensing element. 
Individual Z readings are not required to be ≤ Zeq(limit).  Individual Z readings must 
be >0.4Ω and < 3 MΩ (the upper room temperature impedance limit). Repeat the 
same testing method until all three (3) test locations of the sensing element are 
tested. Then go back and perform the Zeq(Calc) math calculations to assess pass/
fail.
18) Measure and record the “Heated Impedance” using the LCR meter and SCI 
Measurement criteria. Repeat Steps 17) thru 19) for a total of three (3) times within
this test location area (3 readings) with a 3 to 4 (7.62 to 10.16 cm) inch spacing.
NOTE: If the “Heated Impedance” Z value is below the Zeq(limit) for test point 1, 
test point 2, or test point 3, no additional test points within this test location are 
required and can be entered directly on the data sheet as the final Zeq(Calc).
19) Record each value on the data sheet and then use the values to calculate the
Zeq(calc) value using the formula below:
Zeq = 1 / {(1/Z1 + 1/Z2 + 1/Z3)}
The Zeq(calc) value shall be less than or equal to the Zeq(limit) value. Zeq(limit) =
Zeq(snsr) from Table 1 for the salt type sensing element + ½ * CWR measured 
value in Ohms and greater than 0.4Ω.
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20) Log the Zeq(limit) and Zeq(calc) value on the Data Sheet Table 2 (Refer Appendix
A).
NOTE: The Zeq(Calc) limit may be calculated once all 3 test points on a sensing 
element are complete. It is not required to calculate Zeq(Calc) before moving on 
from a test location
21) Remove the heat gun from sensing element and let it cool for at least three (3) 
minutes. A damp cloth can be used to restore sensing element to room
temperature.
a) If the sensing element does not result in a Zeq value less than or equal to the 
limit with the heat gun applied, then check the connections and repeat Steps 
16) thru 19) and if necessary, change the test connection to the sensing
element to the end nearest the test location.
b) If the sensing element does not result in a Zeq value less than or equal to the 
limit with the heat gun applied upon retest, then refer to Section 3.B.(4).(e).2)
Post Test for values that are out of tolerance.
22) Measure and record the “Room Temperature Impedance” after testing the third 
sensing element test location using the LCR meter and SCI Measurement criteria. 
The value must be ≥ 10 kΩ and < 3 MΩ. Log the value on the Data Sheet Table 2 
(Refer Appendix A). Refer to Section 3.B.(4).(e).2) Post Test for values that are out
of tolerance.
23) Run the heat gun on fan only mode for at least five (5) minutes to cool, then turn
off the heat gun.
24) Ensure all data is logged on the Data Sheet Table 2 (Refer Appendix A).
(e) Post test
1) Verify that all sensing element impedance (Z and Zeq(Calc))  measurements are 
within the applicable value limits listed in the attached Data Sheet Table 2 (Refer 
Appendix A). Verify that all test result entries are completed, passing results for 
each sensing element test location or sensing elements tested, and sensing
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KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
element impedance (Z and Zeq(Calc)) measurements are within applicable value 
limits.
2) Any unit that does not meet all requirements of Section 3.B.(4).(d) Test Procedure,
does not meet the requirements of Federal Aviation Administration (FAA) Technical 
Standard Order (TSO)-C11e, is not airworthy and cannot be installed on an aircraft. 
Mark the “Reject” box at the bottom of the Data Sheet Table 2 (Refer Appendix A).
3) Ensure that the sensing element has returned to ambient temperature.
4) Remove LCR meter test leads. Inspect the connector both ends of the CFD sensing
element for damage. Replace the sensing element connector caps if applicable. 
5) Continue to Step 3.C Identification Procedure.
C. Identification Procedure
(1) If the element fails any of the tests, continue to Section 3.C.(5).
(2) For conforming material, mark one face of the connector hex nut.
(3) Carefully recoil the sensing element to the same original coil diameter (approximately 7.5 
inch), taking minimum bend radius into consideration (no kinks permitted), free from bends 
within 1 inch (2.54 cm) of hex nut of sensing element connectors, and replace it in the
original packaging material.
NOTE: Minimum Bend radius is 1 inch (2.54 cm).
(4) Apply a dot to the exterior packaging and insert a copy of the Test Datasheet in the
packaging.
NOTE: The identification procedure must be accomplished in order for the service bulletin 
to be complete.
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
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KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
(5) If unit fails testing, send unit to address below with Record of Accomplishment form filled 
out. Any unit that fails any portion of the test must not be installed/re-installed on an
aircraft.
Collins Aerospace
Attn: CFD NOE Return
4200 Airport Dr.
Wilson, NC 27896
TELEPHONE: 1.888.265.5467
INTERNATIONAL: 1.319.295.5467
FAX NO: 1.319.295.4941
Email: kiddecfdreturns@collins.com
(6) Record of Accomplishment
(a) Record the test results on the form in Appendix A.
NOTE: At the discretion of the OEM/customer, send the Record of Accomplishment to: 
Email: AvionicsSupport@Collins.com
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Page 33 of 33

### Page 35

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Appendix A
APPENDIX A

### Page 36

KIDDE AEROSPACE & DEFENSE
SERVICE BULLETIN
FIRE PROTECTION – CONTINUOUS FIRE DETECTOR (CFD) - FIELD
TESTING OF CFD FOR PROPER OPERATION
Test Datasheet - Bench Top Thermal Test
P/N: Date: ____________
S/N – Date Code: Pre Test Remarks: ____________________________________________________
Test Site Ambient Conditions:
Pre-test sensing element CWR (30 Ω max)
Temperature: °F (°C)
Location
(PN, MID, SN)
Description
Target
Z or Zeq(limit)
(Ω)
Measured
Z
(Ω)
Calculated
Zeq(Calc)
(Ω)
PASS/FAIL 
(Circle One)
Pre-Location 1 Room Temperature Impedance (Z)
≥ 10 kΩ &
< 3 M Ω
N/A
Pass
Fail
Location 1
(         )
Heated Impedance(Z) / Zeq(Calc)
(Zeq(limit) = Zeq(Snsr) from Table 1
+ ½*CWRmeas
> 0.4 Ω &
≤ Zeq(Snsr) + 
½ CWRmeas Ω
≤ _______
*Z1=
Pass
Fail
*Z2=
*Z3=
Pre-Location 2 Room Temperature Impedance (Z)
≥ 10 kΩ &
< 3 M Ω
N/A
Pass
Fail
Location 2
(         )
Heated Impedance(Z) / Zeq(Calc) 
(Zeq(limit) = Zeq(Snsr) from Table 1
+ ½*CWRmeas
> 0.4 Ω &
≤ Zeq(Snsr) + 
½ CWRmeas Ω
≤ _______
*Z1=
Pass
Fail*Z2=
*Z3=
Pre-Location 3 Room Temperature Impedance (Z) ≥ 10 kΩ &
< 3 M Ω
N/A Pass
Fail
Location 3
(         )
Heated Impedance(Z) / Zeq(Calc) 
(Zeq(limit) = Zeq(Snsr) from Table 1
+ ½*CWRmeas
> 0.4 Ω &
≤ Zeq(Snsr) + 
½ CWRmeas Ω
≤ _______
*Z1=
Pass
Fail
*Z2=
*Z3=
Post Test Room Temperature Impedance (Z) ≥ 10 kΩ &< 3 M Ω N/A PassFail
Sensing Element  Performance: Accept [  ] Reject [  ]
Test Technician:
Test Witness:
Date:
Date:
*Individual Z readings are not required to be ≤ Zeq(limit). Individual Z readings must be >0.4Ω and < 3 MΩ (the upper room 
temperature impedance limit).
Table 2: Test Datasheet - Bench Top Thermal Test
February 28/22 CFD-26-1
523-0832620
U.S. Export Classification: EAR 9E991
Appendix A

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