Pottorff Company Model CRD2 ceiling dampers and GBR-CRD ceiling dampers, in combination with the the noted Delta Electronics fan assemblies, are approved for use in fire rated floor-ceiling or roof-ceiling assemblies not exceeding a 3-hr fire-resistance rating for non-combustible construction or not exceeding a 1-hr fire-resistance rating for the combustible assemblies listed below, as an alternative to sheet metal dampers. The maximum number of ceiling dampers in an assembly is based on the approved number of sheet metal dampers in the specified design.
The alternate model name of GBR-CRD is purely a naming option, with no difference from the CRD2 in terms of design, material, or operation.
Model CRD2 ceiling dampers or Model GBR-CRD ceiling dampers have been approved for use with the following ventilation fans:
Delta Electronics, Inc.
- VFB050C4L1
- VFB050C4A1
- VFB080C4L1
- VFB080C4A1
- GBR50L
- GBR50
- GBR80
- GBR80H
- GBR80HL
- GBR80HLED
- GBR80L
- GBR80LED
- GBR80MHL
- GBR80MHLED
- GBR100
- GBR100H
- GBR100HL
- GBR100HLED
- GBR100L
- GBR100LED
- GBR100MHL
- ELT80-110
- ELT80-110LED
- ELT80-110D
- ELT80-110DLED
- ELT80-110H
- ELT80-110HLED
- ELT80-110MH
- ELT80-110MHLED
Model CRD2 ceiling dampers and GBR-CRD ceiling dampers have been approved for installation in floor/ceiling and roof/ceiling assemblies previously rated with a hinged-door sheet metal damper installed in the ceiling and for use with the following 1-hr fire-resistance rated combustible construction floor-ceiling and roof-ceiling UL Listed assembly designs:
- L521
- L546
- L558
- L562
- L574
- L576
- L581
- L583
- L585
- P522
- P533
- P538
- P545
Ventilation fans shall be ducted out of the plenum space using any UL 181 Class 0 or Class 1 duct.
