4-Inch 90-Degree Elbow (Model 4BVL90)

The 4-Inch 90-Degree Elbow (Model 4BVL90) is an essential venting component for residential and commercial HVAC systems. Designed specifically for Type B gas vent applications, this high-quality elbow allows technicians to safely and efficiently change the direction of the venting system around obstacles, framing, or tight mechanical room layouts.

Constructed with durability and safety in mind, this double-wall elbow ensures proper draft and minimizes condensation. Always confirm the required vent diameter and clearance to combustibles before ordering components for your gas appliances.

4-Inch 90-Degree Elbow Features

When routing exhaust gases from Category I appliances such as furnaces, boilers, and water heaters, precision and reliability are non-negotiable. The 4-Inch 90-Degree Elbow offers superior performance and a secure fit for your ductwork and venting needs.

• Size: 4-inch inner diameter for standard B-Vent connections
• Angle: 90-degree directional change for complex layouts
• Design: Double-wall construction for superior insulation
• Compatibility: Fits securely with standard Type B gas vent pipes
• Model: 4BVL90
• Durability: Corrosion-resistant materials for long-lasting performance

Technical Specifications

Safety and Efficiency in Gas Venting

Proper venting is critical to the safe operation of any gas-fired HVAC equipment. The double-wall design of the 4-Inch 90-Degree Elbow provides a layer of insulation that keeps the inner pipe hot to ensure a strong upward draft. Simultaneously, it keeps the outer pipe relatively cool to maintain safe clearances to combustible building materials.

Restricted or improperly routed venting can cause dangerous backdrafts, leading to carbon monoxide buildup within the occupied space. Utilizing a professionally manufactured, UL-Listed elbow ensures smooth airflow with minimal resistance.

Installing the 4-Inch 90-Degree Elbow

Before installing the 4-Inch 90-Degree Elbow, plan your complete vent run to minimize the total number of elbows used, as each sharp turn reduces the overall venting capacity of the system.

Align the elbow with the adjoining pipe sections and secure the connection according to the manufacturer’s locking mechanism. Make sure the joints are fully engaged to prevent dangerous exhaust leaks.

Support the venting system independently to avoid placing excess weight on the elbow or the appliance’s exhaust collar. Always maintain the minimum required clearance to combustibles as dictated by local building codes.

Professional Inspection and Maintenance

Include the 4-Inch 90-Degree Elbow in your annual HVAC maintenance checks. Inspect the outer casing for signs of physical damage, corrosion, or soot accumulation, which could indicate a drafting issue or a blocked flue.

This product includes the elbow only. Straight vent pipes, draft hoods, roof flashings, and termination caps are sold separately. Verify all venting specifications with your equipment manual prior to installation.

Browse more essential venting components in the Xpress Supply Ducting & Venting category. For official guidelines regarding safe gas appliance venting, refer to the National Fuel Gas Code (NFPA 54).