Durozone 35072 Pressure Relief Bypass Damper 12 in Round

Product Description

The DUROZONE 35072 is a round pressure relief bypass damper designed to manage static pressure in forced-air HVAC duct systems. When zone dampers close and system pressure rises, this unit opens to redirect excess airflow and protect the equipment. The damper fits a 12-inch round duct opening and extends 14 inches in length. The blade is constructed from galvanized steel for corrosion resistance. A plated steel counterbalance rod and weight control the opening threshold, and sintered bronze oil-impregnated bushings support smooth, long-lasting operation. HVAC technicians install this damper as part of a zoned residential or light commercial air distribution system.

This damper is suited for residential and light commercial forced-air zoning applications where multiple zone dampers are controlled by a zoning panel. When one or more zones close, static pressure in the supply trunk can climb to levels that stress the blower and heat exchanger. The 35072 mounts inline or as a bypass between supply and return to relieve that pressure passively. The counterbalance rod can be mounted on either side of the damper body, giving installers flexibility when working in tight duct runs or mechanical rooms.

Key Features

• 12-inch round duct connection with 14-inch body length
• Galvanized steel blade construction for corrosion resistance
• Plated steel counterbalance rod and weight for passive pressure relief
• Sintered bronze oil-impregnated bushings for low-friction, maintenance-free pivot operation
• Thumb screws allow easy field adjustment of the counterbalance weight position
• Counterbalance rod mounts on either side to suit various installation orientations

Compatibility

Designed as an OEM-style replacement or new-installation bypass damper for 12-inch round duct systems in residential and light commercial forced-air zoning setups.

Installation Notes

Installation is typically performed by a licensed HVAC technician familiar with zoned forced-air systems. Power down the air handler or furnace at the disconnect before accessing the duct system. The damper should be secured to the ductwork using standard sheet metal screws and sealed with foil-backed tape or mastic to prevent bypass leakage. Adjust the counterbalance weight position using the thumb screws to set the desired relief pressure after the system is commissioned.

Technical Specifications

• Type: Round
• Duct Diameter: 12 inches
• Body Length: 14 inches
• Blade Material: Galvanized Steel
• Bushing Material: Sintered Bronze Oil Impregnated
• Counterbalance Rod Material: Plated Steel

Standard Information

• Brand: DUROZONE
• Manufacturer Part Number: 35072