Duravent 0305INC B-vent Increaser 3x5 Inch Double Wall

Product Description

The DURAVENT 0305INC is a double-wall B-vent increaser fitting designed to transition vent diameter from 3 inches to 5 inches within Category I gas appliance venting systems. Double-wall construction maintains the required clearances to combustibles, keeping the installation compliant with venting codes. This fitting seats between adjacent vent sections and is used wherever a system requires an upsize in vent pipe diameter. Licensed HVAC technicians and gas appliance installers are the typical trades handling this component during new installations and system modifications.

This increaser is applied in residential and light commercial Category I gas appliance venting systems, including natural gas and propane furnaces, water heaters, and boilers that use B-vent pipe. It is positioned inline between vent sections when the system design calls for a diameter change from 3 inches to 5 inches, most commonly when transitioning from an appliance collar to a larger common vent or vertical vent stack.

Key Features

• Increases vent diameter from 3 inches to 5 inches in a single fitting
• Double-wall construction maintains required clearances to combustibles
• Designed for Category I gas appliance B-vent systems
• Installs inline between standard B-vent sections
• Supports proper draft and venting performance through diameter transitions

Compatibility

Designed as an OEM-style replacement and standard fitting for double-wall B-vent systems requiring a 3-inch to 5-inch diameter transition in Category I gas appliance venting applications.

Installation Notes

Installation should be performed by a licensed HVAC technician or qualified gas appliance installer in accordance with NFPA 54 and the appliance manufacturer venting requirements. Shut down and allow the appliance and existing vent sections to cool completely before beginning any vent modifications. Ensure all vent joints are properly secured and that the increaser is oriented to maintain upward draft direction. Verify that the completed vent system meets required clearances to combustibles per local code before returning the appliance to service.

Technical Specifications

• Inlet Diameter: 3 inches
• Outlet Diameter: 5 inches
• Construction: Double Wall
• Vent Type: B-Vent
• Application: Category I Gas Appliance Venting

Standard Information

• Brand: DURAVENT
• Manufacturer Part Number: 0305INC