Type : Motorized Fire Damper
Fire Rating : 21 Series-1½ hour
Blade Type : 3V Single Skin; A : Parallel Operation
MFD B-21 Series is a high performance UL 555 Classified fire damper with 1½hr. fire rating, installed vertically or horizontally (with blades running horizontally) and is rated for airflow in either direction.
Fire Rating : 1½ hrs.
Max Velocity : 2000 fpm
Max Operating Pressure: 4 in. w.g (1000 pa)
16 gauge (1.4 mm – 1.7 mm) thick galvanized steel.
Parallel operated 3 ‘V’ type blade made of 16 gauge (1.4 mm – 1.7 mm) thick galvanized steel.
12 mm diameter Galvanized steel shaft.
Honeywell, Belimo, Seimens (24V AC, 120V AC, 230V AC).
Minimum 0.9 mm, single section is field or factory installed.
Multiple section is factory installed.
Sleeve thickness as per NFPA table 3-4.6.3
Fire resistant bronze bush.
For BMS open / close indication.
1½” x 1½” x 16 gauge (40 x 40 x 1.5 mm).
Silicon rubber blade seals.
Externally mounted open / close visible indicator.
Manual reset for damper.
Neck adapter for round duct connections.
Model : MFD-GB-D-21-A UL 555 Damper meets the required standards of SMACNA, NFPA, IBC, BOCA, ICBO, UL.
Actuator location standard: Left side from rear view
(Jack shaft view)
FC : Fail Close in the event of Fire
Frame : Stainless Steel 16 gauge (304/316L)
Blade : Stainless Steel 16 gauge (304/316L)