5" x 60" Round Pipe, Type B Gas Vent

Details

Model: 5M5
Manufacturer: Metal-Fab, Inc.
Product Name: Type B Gas Vent Pipe – Series M
Part Number: 1842049
Description: Double-wall Type B vent pipe, 5-inch diameter, 5-foot length, aluminum inner liner, galvanized steel outer wall, UL-listed for Category I gas appliances.

Product Overview

The Metal-Fab 5M5 Type B Gas Vent Pipe is a UL-listed, double-wall venting component designed for use with Category I natural draft gas-fired appliances, including furnaces, boilers, and water heaters. The vent features an aluminum inner flue and a galvanized steel outer casing, providing corrosion resistance and thermal performance while maintaining reduced clearance to combustible materials. The 5-inch diameter, 5-foot section is part of Metal-Fab’s M-Series system, engineered for secure joint locking and simplified alignment in residential, light commercial, and multifamily venting applications. The precision-rolled end design allows for fast, safe installation without field fabrication.

Technical Specifications

• Manufacturer Part Number: 5M5
• Alternate Part Number: 1842049
• Series: M-Series Type B Gas Vent
• Vent Type: Type B Double-Wall Gas Vent
• Inner Material: Aluminum alloy (corrosion-resistant)
• Outer Material: Galvanized steel
• Nominal Diameter: 5 inches (127 mm)
• Length: 60 inches (5 feet / 1.52 meters)
• Wall Construction: Double-wall, air-insulated design
• Wall Thickness: 1/4 inch nominal
• Connection Type: Twist-lock joint with positive stop
• Clearance to Combustibles: 1 inch (per UL 441 listing)
• Maximum Operating Temperature: 480°F (249°C)
• Appliance Category: Category I (natural draft, non-positive pressure)
• Application: Gas-fired furnaces, boilers, unit heaters, and water heaters
• Installation Orientation: Vertical or offset as permitted by code
• Compliance: UL 441, NFPA 54 (National Fuel Gas Code), ICC Standard Fuel Gas Code
• Finish: Mill aluminum (inner), galvanized steel (outer)
• Weight: Approx. 2.8 lb per linear foot (varies by diameter)
• Use Environment: Indoor venting applications where combustion gas temperatures remain below condensation threshold

Installation Notes

• Verify appliance category and vent sizing per NFPA 54 and manufacturer’s tables before installation.
• Align and engage the twist-lock connections fully to ensure positive mechanical locking between sections.
• Maintain minimum 1-inch clearance from combustibles along the entire vent run.
• Support vertical runs at intervals per code using approved wall straps or joist hangers.
• Terminate with a UL-listed Type B vent cap; ensure proper draft hood connection at appliance outlet.
• Do not mix venting components from different manufacturers within a single system.

Summary

The Metal-Fab 5M5 Type B Gas Vent Pipe is a 5-inch diameter, 5-foot-long double-wall vent section designed for Category I gas appliance venting. Featuring aluminum inner and galvanized steel outer construction, it provides reduced clearance to combustibles, efficient draft performance, and quick twist-lock assembly. This component meets UL 441 and NFPA 54 standards for professional installation in residential and light commercial systems.