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Pottorff > Ceiling Radiation Dampers > Ceiling Radiation Dampers > Wood Truss Systems > CFD-521-90

Model CFD-521-90

1 Hour - Ceiling Radiation Damper
90° Plenum

The CFD-521-90 ceiling radiation damper employs butterfly style blades for point-of-origin control of radiant heat in HVAC systems. The CFD-521-90 is installed horizontally in the ceiling membrane of combustible and non-combustible assemblies with a fire-resistance rating up to and including 1 hour.

CFD-521-90 90° Plenum

Standard Construction

Frame: 22 gauge (0.85) galvanized steel.

Plenum Outlet Box: 28 gauge (0.47) galvanized steel.

Blades: 22 gauge (0.85) galvanized steel – butterfly insulated with ceramic refractory material.

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

Fire Closure Device: Fusible link.

Fire Closure Temperature: 165°F (75°C).

Minimum Size:
Grille Opening — 4" x 6" (102 x 152)
Duct — 4" Ø (102 Ø).

Maximum Size:
Grille Opening — Square: 12" x 12" (305 x 305)
Rectangular: 14" (356) W x 10" (254) H (90o plenum), 10" (254) W x 14 (356) H (end plenum) with a maximum area of 144 in2 (929 cm2) Duct - 10” Ø (254 Ø)


UL 555C Fire Resistance Rating: 1 hour (horizontal, for use in UL assemblies L-521, L-528, L-546, L-558, L-562, L-574, L-576, L-581, L-583, L-585, M-509, M-540, P-522, P-533, P-538, P-545 and P-547.

UL 555C listing: R14603

CSFM listing: 3226-0368:104

Meets NFPA Standards: 90A and 101

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

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