Honeywell mgii-12 Barometric Draft Damper 12 in

Product Description

The HONEYWELL mgii-12 is a standard barometric draft damper designed to maintain consistent negative draft pressure in vented combustion appliance flue systems. The unit includes an integral collar for straightforward duct connection and is rated for use with natural gas, oil, wood, and coal-fired appliances. Barometric draft controls are passive, counterweighted dampers that open and close automatically in response to flue pressure changes, protecting the appliance from over-draft or backdraft conditions. This 12-inch model is sized for mid-to-large residential or light commercial heating equipment and is a field-installed component typically handled by licensed HVAC or heating technicians.

The mgii-12 is suited for installation in single-wall or double-wall flue connector piping downstream of the appliance draft hood or flue outlet. It is appropriate for use in residential and light commercial heating systems burning natural gas, fuel oil, wood, or coal. The included collar allows direct connection into the flue pipe without requiring additional adapters in standard installations. Applications include forced-air furnaces, boilers, water heaters, and solid-fuel appliances that require draft regulation at the flue connector.

Key Features

• 12-inch diameter sizing for mid-to-large residential and light commercial flue systems
• Compatible with natural gas, fuel oil, wood, and coal-fired appliances
• Includes integral collar for direct flue pipe connection
• Passive counterweighted design requires no electrical connection
• Automatically modulates to maintain consistent negative draft pressure

Compatibility

Designed as an OEM-style barometric draft control for 12-inch flue connector piping on natural gas, oil, wood, and coal-fired residential and light commercial heating appliances.

Installation Notes

Installation should be performed by a licensed HVAC or heating technician in accordance with applicable local codes and the appliance manufacturer instructions. Shut down and allow the appliance to cool completely before working on the flue system. The damper must be positioned correctly in the flue connector with the pivot axis oriented horizontally and the counterweight adjusted per the manufacturer setup procedure. Verify draft performance after installation using a draft gauge before returning the appliance to service.

Technical Specifications

• Diameter: 12 inches
• Fuel Type Compatibility: Natural Gas, Oil, Wood, Coal
• Collar: Included
• Control Type: Barometric Draft Damper

Standard Information

• Brand: HONEYWELL
• Manufacturer Part Number: mgii-12