{"product_id":"southwark-metal-fb_21-1-2x28-1-2-return-air-furnace-box","title":"Southwark Metal fb_21-1\/2x28-1\/2 Return Air Furnace Box","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe SOUTHWARK METAL fb_21-1\/2x28-1\/2 is a return air sheet metal furnace box fabricated from 26-gauge hot dip galvanized steel. It measures 21.5 inches by 28.5 inches by 18.5 inches and is built to serve as the return air plenum box in residential and light commercial forced-air heating systems. The hot dip galvanization process provides corrosion resistance suited to HVAC duct environments. This type of component is typically installed by licensed HVAC technicians or sheet metal contractors as part of a furnace duct system assembly.\u003c\/p\u003e\u003cp\u003eThis furnace box is intended for return air applications in residential and light commercial HVAC installations. It is sized to fit standard furnace openings requiring a 21.5-inch by 28.5-inch face dimension with an 18.5-inch depth. The unit meets applicable industry standards set by ACCA and SMACNA, making it appropriate for installations where code-compliant duct construction is required. It is suited for new construction and replacement duct work in forced-air gas or electric furnace systems.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e26-gauge hot dip galvanized steel construction for durability and corrosion resistance\u003c\/li\u003e\n\u003cli\u003eReturn air configuration for use as a furnace plenum or duct box\u003c\/li\u003e\n\u003cli\u003eDimensions of 21.5 inches by 28.5 inches by 18.5 inches for standard furnace fitment\u003c\/li\u003e\n\u003cli\u003eCompliant with ACCA and SMACNA standards for sheet metal duct construction\u003c\/li\u003e\n\u003cli\u003eApplicable for both residential and light commercial HVAC systems\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as an OEM-style sheet metal return air furnace box for residential and light commercial forced-air HVAC systems requiring a 21.5-inch by 28.5-inch by 18.5-inch return air plenum box built to ACCA and SMACNA standards.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eInstallation should be performed by a licensed HVAC technician or qualified sheet metal contractor in accordance with SMACNA duct construction standards and local mechanical codes. Shut down and lock out the furnace and air handler before beginning any duct work. Seal all seams with code-approved duct sealant or mastic to meet ACCA Manual D airflow requirements. Do not use this box in supply air applications; it is rated for return air service only.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimensions\u003c\/strong\u003e: 21.5 inches x 28.5 inches x 18.5 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Hot Dip Galvanized Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGauge\u003c\/strong\u003e: 26\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBox Type\u003c\/strong\u003e: Return Air\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplicable Standards\u003c\/strong\u003e: ACCA, SMACNA, NATE\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication\u003c\/strong\u003e: HVAC, Residential and Light Commercial\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: SOUTHWARK METAL\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: fb_21-1\/2x28-1\/2\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SOUTHWARK METAL","offers":[{"title":"Default Title","offer_id":51268811948338,"sku":"FB_21-1\/2X28-1\/2","price":140.08,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/308911425.jpg?v=1780706493","url":"https:\/\/voomisupply.com\/products\/southwark-metal-fb_21-1-2x28-1-2-return-air-furnace-box","provider":"Voomi Supply","version":"1.0","type":"link"}