{"product_id":"premium-lesso-blue-upvc-spring-check-valve-20-32mm-true-union-non-return-valve-aquarium-anti-siphon-plumbing","title":"Premium Lesso Blue UPVC Spring Check Valve (20-32mm)  True Union Non-Return Valve  Aquarium Anti-Siphon Plumbing","description":"\u003cdiv style=\"background-color: #f8f9fa; padding: 10px; border-left: 4px solid #dc3545; margin-bottom: 20px;\"\u003e\u003cp style=\"margin: 0;\"\u003e\u003cem\u003e🔄 Have a shallow tank with less than 1 meter of backpressure? You MUST use our gravity-based \u003cstrong\u003e\u003ca href=\"https:\/\/atradesen.com\/collections\/watering-irrigation\/products\/premium-upvc-clear-lift-check-valve-20-32mm-silent-aquarium-anti-siphon-non-return-valve-true-union-plumbing\" style=\"color: #dc3545; text-decoration: underline;\"\u003eClear Lift Check Valves\u003c\/a\u003e\u003c\/strong\u003e instead for a proper low-pressure seal!\u003c\/em\u003e\u003c\/p\u003e\u003c\/div\u003e\u003ch2\u003ePremium Lesso Blue UPVC Spring Check Valve\u003c\/h2\u003e\u003cp\u003eProtect your water pump and living room from catastrophic power-outage floods with the Lesso Blue Spring-Loaded Check Valve from \u003cstrong\u003eAtradesen.com\u003c\/strong\u003e. Featuring a heavy-duty internal spring mechanism and a True Union quick-release design, this premium non-return valve ensures water only flows one way while maintaining a professional, color-coded blue aesthetic for your custom sump.\u003c\/p\u003e\u003ch3\u003e🌟 Advanced Maintenance \u0026amp; Plumbing Features\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eInternal Spring Mechanism:\u003c\/strong\u003e Provides a rapid, forceful closure the moment your water pump stops, blocking massive amounts of water from back-siphoning into your sump.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTrue Union Quick-Release:\u003c\/strong\u003e The center nut can be unscrewed by hand, allowing you to instantly detach and clean the internal valve core without ever cutting your glued PVC pipes!\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSafe \u0026amp; Permanent Seal:\u003c\/strong\u003e Made from non-toxic UPVC. Creates a leak-proof cold-weld joint when used with standard PVC adhesive cement.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003e🚨 CRUCIAL INSTALLATION \u0026amp; BACKPRESSURE WARNING\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eBecause this valve utilizes an internal spring, it requires a specific physical setup to seal 100%. Please read Atradesen.com's rules carefully:\u003c\/p\u003e\u003cul style=\"background-color: #f8d7da; padding: 15px 15px 15px 35px; border-radius: 5px; color: #721c24; border: 1px solid #f5c6cb;\"\u003e\n\u003cli\u003e\n\u003cstrong\u003e⚠️ 1-METER BACKPRESSURE REQUIREMENT:\u003c\/strong\u003e To fully compress the internal seal, the reverse water column (backpressure) dropping onto the valve during a power outage \u003cb\u003eMUST be greater than 1 Meter (approx. 3.3 feet or ≥0.01 MPA).\u003c\/b\u003e If your return pipe is shorter than 1 meter, the water weight will not be heavy enough to push the spring closed, resulting in a slow, continuous leak!\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e🚨 SIZING LOGIC (Inner Dia. matches Outer Dia.):\u003c\/strong\u003e The sizes listed (e.g., 25mm) refer to the \u003cb\u003eInner Diameter (I.D.)\u003c\/b\u003e of the sockets. They are designed to sleeve \u003cb\u003eOVER\u003c\/b\u003e your rigid PVC pipes with a matching Outer Diameter (O.D.).\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Atradesen","offers":[{"title":"20mm I.D. (With Internal Spring)","offer_id":56643656843430,"sku":null,"price":3.68,"currency_code":"USD","in_stock":true},{"title":"25mm I.D. (With Internal Spring)","offer_id":56643656876198,"sku":null,"price":4.65,"currency_code":"USD","in_stock":true},{"title":"32mm I.D. (With Internal Spring)","offer_id":56643656908966,"sku":null,"price":6.58,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0739\/2588\/6118\/files\/Premium_Lesso_Blue_UPVC_Spring_Check_Valve_20-32mm_True_Union_Non-Return_Valve_Aquarium_Anti-Siphon_Plumbing-002.png?v=1781251748","url":"https:\/\/atradesen.com\/products\/premium-lesso-blue-upvc-spring-check-valve-20-32mm-true-union-non-return-valve-aquarium-anti-siphon-plumbing","provider":"Atradesen","version":"1.0","type":"link"}