{"product_id":"flexduct-1840-rip-stop-flex-duct-18-in-25-ft-r4-2","title":"Flexduct 1840 Rip Stop Flex Duct 18 in 25 Ft R4.2","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe FLEXDUCT 1840 is an 18-inch inside diameter, 25-foot rip stop insulated flexible duct designed for residential and commercial HVAC air distribution systems. Built to the 40 Series specification, it uses a tri-layer construction of polyester, fiberglass, and metalized polyester to deliver R4.2 thermal insulation and a vapor transmission rate of 0.05 or less. The duct supports airflow up to 6000 feet per minute (fpm), making it suitable for high-volume trunk and branch runs. The silver metalized outer jacket resists moisture and maintains jacket integrity under normal mechanical handling. Licensed HVAC technicians and sheet metal mechanics are the primary installers of this product.\u003c\/p\u003e\n\u003cp\u003eThe FLEXDUCT 1840 is used in forced-air heating and cooling systems where large-diameter flexible duct runs are required. Its 18-inch bore accommodates high-capacity air handlers and rooftop units rated up to approximately 15 tons. Typical installations include runs from plenum boxes to large diffusers, bypass ducts, and return-air connections in commercial light construction, large residential applications, and equipment rooms. The rip stop inner core resists tearing during installation routing through tight spaces or over structural obstacles.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e18-inch inside diameter supports high-volume airflow up to 6000 fpm, rated for approximately 15-ton systems\u003c\/li\u003e\n  \u003cli\u003eR4.2 fiberglass insulation blanket reduces thermal losses along the duct run\u003c\/li\u003e\n  \u003cli\u003eVapor transmission rate of 0.05 or less minimizes condensation risk on the duct exterior\u003c\/li\u003e\n  \u003cli\u003eRip stop inner liner construction resists tearing and puncture during installation\u003c\/li\u003e\n  \u003cli\u003ePressure rating of -0.5 to 10 inches water column covers both supply and return applications\u003c\/li\u003e\n  \u003cli\u003eTemperature rated from -20 degrees F to 180 degrees F for use in unconditioned attics, crawlspaces, and mechanical rooms\u003c\/li\u003e\n  \u003cli\u003eDomestic manufacture with silver metalized polyester outer jacket\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003eDesigned as an OEM-style replacement or new-installation flexible duct for forced-air HVAC systems requiring an 18-inch inside diameter connection. Suitable for supply and return applications on air handlers and rooftop units in the 40 Series flexible duct category.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003eInstallation should be performed by a licensed HVAC technician or sheet metal mechanic in accordance with SMACNA flexible duct installation standards and local mechanical codes. Power down the air handling unit and lock out the disconnect before making duct connections. Avoid sharp bends that exceed the minimum bend radius of the duct, as compressed or kinked sections significantly increase static pressure and reduce airflow. Secure both ends with approved draw bands or clamps and seal with mastic or listed duct tape per code requirements.\u003c\/p\u003e\n\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInside Diameter\u003c\/strong\u003e: 18 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eLength\u003c\/strong\u003e: 25 feet\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlow Rate\u003c\/strong\u003e: 6000 fpm (approximately 15 ton capacity)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInsulation Value\u003c\/strong\u003e: R4.2\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePressure Rating\u003c\/strong\u003e: -0.5 to 10 inches water column\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTemperature Rating\u003c\/strong\u003e: -20 degrees F to 180 degrees F\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eVapor Transmission\u003c\/strong\u003e: 0.05 or less\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Polyester, Fiberglass, Metalized Polyester\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFinish\u003c\/strong\u003e: Silver\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSeries\u003c\/strong\u003e: 40 Series\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eType\u003c\/strong\u003e: Rip Stop Insulated\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePackage Dimensions\u003c\/strong\u003e: 31 inches L x 23 inches W x 31 inches H\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 31.53 pounds\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOrigin\u003c\/strong\u003e: Domestic\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eStandard Information\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: FLEXDUCT\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 1840\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"FLEXDUCT","offers":[{"title":"Default Title","offer_id":51307001315634,"sku":"1840","price":130.9,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/309549149.png?v=1781304595","url":"https:\/\/voomisupply.com\/products\/flexduct-1840-rip-stop-flex-duct-18-in-25-ft-r4-2","provider":"Voomi Supply","version":"1.0","type":"link"}