Quietflex 1880 Flexible Foil Air Duct 18 in 25 Ft R6

Product Description

The QUIETFLEX 1880 is an R6-insulated flexible foil air duct designed for residential, commercial, and manufactured home HVAC distribution systems. It ships in a 25-foot length with an 18-inch diameter, making it well suited for large trunk-to-branch runs where thermal performance and pressure integrity matter. The outer jacket is a metalized polyester film reinforced with a rip-stop scrim that resists tearing during installation and service. The inner liner is supported by fiberglass insulation rated at R6. Rated for continuous operation from -20 to 180 degrees F and intermittent peaks to 200 degrees F, this duct handles the full range of forced-air heating and cooling conditions.

This duct is used in ducted split systems, package units, air handlers, and ventilation layouts where large-diameter flexible runs are required. The 18-inch diameter suits high-volume supply or return applications in light commercial and larger residential builds. HVAC installers working on new construction or retrofit projects will find this length practical for runs that would otherwise require multiple shorter sections. Quietflex produces flexible duct from 3 inches through 22 inches in R4.2 and R6 configurations, and the 1880 fits within that commercial and residential product line.

Key Features

• R6 fiberglass insulation for thermal efficiency in supply and return air applications
• Metalized polyester vapor barrier jacket with rip-stop scrim reinforcement for tear resistance
• 10 inches WC positive pressure rating for compatibility with high-static air systems
• Velocity rating of 6000 feet per minute suits high-volume airflow applications
• Temperature range of -20 to 180 degrees F continuous, -20 to 200 degrees F intermittent
• 18-inch diameter in a 25-foot length reduces spliced-section counts on longer runs

Compatibility

Designed for use in residential, commercial, and manufactured home ducted HVAC systems requiring large-diameter flexible duct. Suitable for new construction and retrofit installations using standard 18-inch duct connections and fittings.

Installation Notes

Installation should be performed by a licensed HVAC technician in accordance with SMACNA guidelines and local mechanical codes. Power the air handler or furnace off at the disconnect before connecting or repositioning duct sections. Support flexible duct at manufacturer-recommended intervals to prevent excessive sag, which reduces airflow and increases static pressure. Avoid sharp bends that collapse the inner liner; maintain the minimum bend radius specified by the duct manufacturer.

Technical Specifications

• Diameter: 18 inches
• Length: 25 feet
• R-Value: R6
• Pressure Rating: 10 inches WC positive, 0.5 inches WC negative
• Velocity Rating: 6000 fpm
• Temperature Rating: -20 to 180 degrees F continuous, -20 to 200 degrees F intermittent
• Material: Metalized Polyester / Fiberglass
• Color: Silver

Standard Information

• Brand: QUIETFLEX
• Manufacturer Part Number: 1880