{"id":790,"date":"2023-04-08T06:02:13","date_gmt":"2023-04-08T06:02:13","guid":{"rendered":"http:\/\/gerhman.com\/?post_type=product&#038;p=790"},"modified":"2025-09-15T11:16:51","modified_gmt":"2025-09-15T11:16:51","slug":"nrdr-backdraft-damper-for-round-ducts","status":"publish","type":"product","link":"https:\/\/gerhman.com\/fr\/produit\/nrdr-backdraft-damper-for-round-ducts\/","title":{"rendered":"NRDR &#8211;  backdraft damper for round ducts"},"content":{"rendered":"<div class=\"page\" title=\"Page 3\">\n<div class=\"section\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p>Backdraft dampers also named non return dampers type \u2018NRDR\u2019, are designed for use intake and discharge opening in commercial and residential round ducting air conditioning systems. When the ventilation system is on, the blades of the non-return damper are held in the open position by the airflow. If the system is switched off, the damper blades close automatically, thus preventing reverse airflow and giving protection against the ingress of untempered air, rain and birds into the air conditioning system.<\/p>\n<p><strong>Features<\/strong><\/p>\n<ul>\n<li>For automatic shutoff of the air ducts and prevention of back drafting when the fan is off. Suitable for installation in various premises.<\/li>\n<li>Compatible with \u2205 100 up to 315 mm round air ducts.<\/li>\n<\/ul>\n<\/div>\n<div class=\"page\" title=\"Page 3\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p><strong>Design<\/strong><\/p>\n<ul>\n<li>Galvanized steel case.<\/li>\n<li>Two spring loaded blades made of aluminium.<\/li>\n<li>Blades are opened by air pressure and are closed with a spring.<\/li>\n<\/ul>\n<\/div>\n<div class=\"page\" title=\"Page 3\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p><strong>Mounting<\/strong><\/p>\n<ul>\n<li>Fixing to round ducts with clamps.<\/li>\n<li>Provide vertical position of\u00a0blade axis.<\/li>\n<li>Install the backdraft damper into the ventilation system with respect to the air flow direction.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>Backdraft dampers also named non return dampers type \u2018NRDR\u2019, are designed for use intake and discharge opening in commercial and residential round ducting air conditioning systems.<span class=\"excerpt-hellip\"> [\u2026]<\/span><\/p>\n","protected":false},"featured_media":792,"comment_status":"open","ping_status":"closed","template":"","meta":[],"product_brand":[],"product_cat":[41,42,44],"product_tag":[80],"class_list":{"0":"post-790","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-airflow-management","7":"product_cat-control-dampers","8":"product_cat-overflow-units","9":"product_tag-heavy","11":"first","12":"instock","13":"shipping-taxable","14":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/product\/790","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/comments?post=790"}],"version-history":[{"count":1,"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/product\/790\/revisions"}],"predecessor-version":[{"id":793,"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/product\/790\/revisions\/793"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/media\/792"}],"wp:attachment":[{"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/media?parent=790"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/product_brand?post=790"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/product_cat?post=790"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/gerhman.com\/fr\/wp-json\/wp\/v2\/product_tag?post=790"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}