MFD-GB-30-A-R Fire Damper - 3-Hour Rated Round Duct

Ensure maximum fire safety and compartmentation in your HVAC systems with the MFD-GB-30-A-R fire damper. Designed specifically for round duct connections, this damper meets UL-555 standards with a verified 3-hour fire rating, providing critical protection against the spread of fire and smoke through ventilation shafts.

Robust Construction & Materials

The damper features a standard construction frame made of 16-gauge (1.4 mm - 1.7 mm) thick galvanized steel, ensuring durability and resistance to corrosion. The blades are parallel-operated, 3 'V' type blades, also crafted from 16-gauge galvanized steel, providing a tight seal when closed. To maintain integrity under high temperatures, the jamb seals are made of stainless steel, while the blade seals utilize high-performance silicon rubber.

Key Components & Functionality

• Thermal Response Device (TRD): Equipped with a TRD set to 165°F (74°C) to automatically close the damper upon detecting fire.
• Actuator Options: Compatible with Honeywell actuators in 24V AC, 120V AC, or 230V AC configurations.
• Jack Shaft: ½” x ½“ (12 mm) galvanized steel square shaft for reliable operation.
• Control Interface: Includes limit switches for BMS open/close indication, an externally mounted visual indicator, and a manual reset push button.
• Mounting & Fittings: Comes with retaining angles (1½” x 1½” x 16 gauge) and a junction box for easy electrical integration.

Compliance & Standards

This damper complies with SMACNA, NFPA, IBC, BOCA, ICBO, and UL standards. The sleeve thickness adheres to NFPA Table 3-4.6.3 requirements, with fire-resistant bronze bushes included for smooth operation. Note that this model is Fail Close (FC) in the event of a fire, ensuring the duct is sealed to contain the threat.