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Pottorff > Ceiling Radiation Dampers > Ceiling Radiation Dampers > Wood Truss Systems > CFD-521

Model CFD-521

1 Hour - Ceiling Radiation Damper
Butterfly Style Blade

The CFD-521 ceiling radiation damper employs butterfly style blades for point-of-origin control of radiant heat in HVAC systems. The CFD-521 is installed horizontally in the ceiling membrane of combustible floor-ceiling or roof-ceiling assemblies with fire resistance ratings up to and including 1 hour.

CFD-521 Butterfly Style Blade

Standard Construction

Frame: 22 ga. (1) galvanized steel with integral outlet box.

Blades: 22 ga. (0.85) galvanized steel - butterfly. Insulated with ceramic refractory material for dampers larger than 114 in2 (735 cm2).

Transition: Round, with 2" (51) deep collar, located on W side of outlet box.

Plaster Ground: 5/8" (16) deep x 1" (25) wide.

Closure Device: Fusible Link.

Fire Closure Temperature: 165oF (75oC).

Minimum Size: 4" x 6" (102 x 152)

Maximum Size:
Square: 18" x 18" (457 x 457)
Rectangular: 24" (610) W or 20" (508) H with a maximum area of 324 in2 (2090 cm2)


UL 555C Fire Resistance Rating: 1 hour for installation in floor designs L-521, L-528, L-546, L-558, L-562, L-574, L-576, L-581, L-583, L-585, M-509, M-540 and in roof/ceiling designs P-522, P-533, P-538, P-545, P-547, P-579 and P-580.

UL 555C Listing: R14603

CSFM Listing: 3226-0368:104

Warnock Hersey Listing #: WHI-495-PSH-0177, -0178

Meets NFPA Standards: 90A and 101

Meets Building Code Standards: IBC, NBC, NFPA, SBC and UBC

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