Quietflex 14KM Flex Duct 14 Inch R-4.2 Foil Jacket 25 Foot

Product Description

The QUIETFLEX 14KM is a 14-inch diameter flexible duct designed for supply and return air distribution in residential and light commercial HVAC systems. It ships in a 25-foot length and carries an R-4.2 insulation value, providing solid thermal performance to limit heat gain and loss along the duct run. The foil outer jacket resists tearing and moisture, protecting the insulation layer during and after installation. The flexible inner core supports smooth, low-turbulence airflow and helps reduce system noise. HVAC technicians and installers use this duct where a large-diameter flex run is needed to move high volumes of conditioned air efficiently.

This flex duct is suited for residential forced-air systems and light commercial applications where supply or return air runs require a 14-inch diameter connection. Common installation scenarios include main trunk branch takeoffs, large air handler supply plenums, and return air drops in open-framing or attic runs. The 25-foot coil length reduces the number of connections needed on longer runs, limiting potential leak points and simplifying rough-in.

Key Features

• 14-inch diameter inner core sized for high-volume airflow on large residential and light commercial systems
• R-4.2 insulation value reduces heat transfer along the duct run
• Foil outer jacket provides moisture resistance and durability against tearing
• 25-foot length minimizes the number of field connections on longer runs
• Flexible construction allows routing around framing obstructions without rigid fittings

Compatibility

Designed as an OEM-style flexible duct replacement and new-installation option for 14-inch diameter supply and return air connections in residential and light commercial forced-air HVAC systems.

Installation Notes

Installation is typically performed by a licensed HVAC technician or sheet metal contractor in accordance with SMACNA flexible duct installation standards and local mechanical codes. Power down and lock out the air handler or furnace before making duct connections. Avoid sharp bends that reduce the inner diameter and restrict airflow; maintain the largest bend radius possible and keep the duct fully extended to prevent compression losses. Secure all connections with approved clamps and mastic or metal-backed tape rated for flexible duct.

Technical Specifications

• Diameter: 14 inches
• Length: 25 feet
• Insulation R-Value: R-4.2
• Outer Jacket: Foil

Standard Information

• Brand: QUIETFLEX
• Manufacturer Part Number: 14KM