{"product_id":"pvc-one-way-non-return-flap-check-valve-id-20-25-32-40-50-63mm","title":"PVC One Way Non Return Flap Check Valve Pipe Fittings ID 20 25 32 40 50 63 mm","description":"\u003cdiv class=\"hdiy-desc\"\u003e\n\n\u003cdiv class=\"hdiy-overview\"\u003e\n\u003ch2\u003ePVC Non Return Flap Check Valve — Stop Backflow in Water, Drainage \u0026amp; Irrigation Pipe Systems\u003c\/h2\u003e\n\u003cp\u003eWhen a pump shuts off or pressure drops, uncontrolled backflow can contaminate supply lines, flood drainage channels, or damage equipment. Plumbers, irrigation installers, and DIY builders who need a reliable one-way flow solution turn to a PVC flap check valve — a passive, maintenance-light fitting that closes automatically the moment flow reverses.\u003c\/p\u003e\n\u003cp\u003eEach PVC one-way non-return flap check valve is moulded from rigid PVC with a hinged internal flap. Available in inner diameter sizes of 20mm (≈¾\"), 25mm (≈1\"), 32mm (≈1¼\"), 40mm (≈1½\"), 50mm (≈2\"), and 63mm (≈2½\"), and in two finishes — Dark Grey (standard PVC) and Transparent (for visual flow confirmation). The socket ends accept standard PVC pipe of the corresponding ID for solvent-cement jointing.\u003c\/p\u003e\n\u003cp\u003eTypical use cases include residential and commercial cold-water supply lines, drip and sprinkler irrigation return-prevention, pond and aquarium pump outlets, rainwater harvesting downpipes, and grey-water drainage systems where backflow prevention is required without an active valve.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"hdiy-compat\"\u003e\n\u003cspan class=\"hdiy-compat-icon\"\u003e🔗\u003c\/span\u003e\n\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Fits standard PVC pressure pipe (PN10\/PN16) and drainage pipe of matching inner diameter. Solvent-cement socket ends. Not rated for hot water or steam service. Verify pipe OD against your existing fittings before ordering.\n\u003c\/div\u003e\n\n\u003cdiv class=\"hdiy-features\"\u003e\n\u003ch2\u003e✅ Key Features of These PVC Non Return Flap Check Valves\u003c\/h2\u003e\n\u003cdiv class=\"hdiy-list\"\u003e\n\u003cdiv\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🔄\u003c\/span\u003e\u003cstrong\u003eAutomatic One-Way Flow Control\u003c\/strong\u003e\u003cbr\u003eThe hinged internal flap opens under forward flow pressure and closes by gravity and back-pressure the instant flow stops or reverses — no manual operation required.\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cspan class=\"hdiy-icon\"\u003e📐\u003c\/span\u003e\u003cstrong\u003eSix Inner Diameter Options\u003c\/strong\u003e\u003cbr\u003eAvailable in ID 20, 25, 32, 40, 50, and 63mm to match the most common PVC pipe sizes used in residential and light-commercial plumbing and irrigation.\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cspan class=\"hdiy-icon\"\u003e👁️\u003c\/span\u003e\u003cstrong\u003eTransparent or Dark Grey Body\u003c\/strong\u003e\u003cbr\u003eChoose Dark Grey for standard installations, or Transparent to visually confirm flow direction and flap operation without disassembling the line.\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🧪\u003c\/span\u003e\u003cstrong\u003eRigid PVC Construction\u003c\/strong\u003e\u003cbr\u003eMoulded from rigid PVC, which resists corrosion, scale build-up, and most common water treatment chemicals — suitable for cold-water and irrigation service.\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🔧\u003c\/span\u003e\u003cstrong\u003eSolvent-Cement Socket Ends\u003c\/strong\u003e\u003cstrong\u003e\u003c\/strong\u003e\u003cbr\u003eBoth ends are socket-type for standard PVC solvent cement jointing, creating a leak-free, permanent bond compatible with PN10\/PN16 pipe systems.\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cspan class=\"hdiy-icon\"\u003e⚖️\u003c\/span\u003e\u003cstrong\u003eLow Cracking Pressure\u003c\/strong\u003e\u003cbr\u003eThe lightweight flap design opens at low differential pressure, minimising flow restriction in gravity-fed and low-pressure pump systems.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"hdiy-table-wrap\"\u003e\n\u003ch2\u003e📐 Technical Specifications — PVC Flap Check Valve\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eProduct Type\u003c\/th\u003e\n\u003ctd\u003eOne-Way Non-Return Flap Check Valve\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eBody Material\u003c\/th\u003e\n\u003ctd\u003eRigid PVC (Polyvinyl Chloride)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFlap Material\u003c\/th\u003e\n\u003ctd\u003ePVC \/ flexible polymer (varies by size)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eAvailable Inner Diameters\u003c\/th\u003e\n\u003ctd\u003e20mm, 25mm, 32mm, 40mm, 50mm, 63mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eColour \/ Finish\u003c\/th\u003e\n\u003ctd\u003eDark Grey; Transparent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eEnd Connection Type\u003c\/th\u003e\n\u003ctd\u003eSocket (solvent-cement)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCompatible Pipe Standard\u003c\/th\u003e\n\u003ctd\u003eStandard PVC pressure pipe PN10\/PN16\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMax Working Pressure\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTemperature Range\u003c\/th\u003e\n\u003ctd\u003eCold water service only (typically 0–45°C \/ 32–113°F)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFlow Direction\u003c\/th\u003e\n\u003ctd\u003eOne-way (marked on body)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eInstallation Orientation\u003c\/th\u003e\n\u003ctd\u003eHorizontal or vertical (upward flow); confirm per size\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eQuantity per Order\u003c\/th\u003e\n\u003ctd\u003e1 piece per variant\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"hdiy-faq\"\u003e\n\u003ch2\u003e❓ Frequently Asked Questions\u003c\/h2\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWhich inner diameter should I choose for my pipe?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eMatch the ID of the valve to the outer diameter (OD) of your PVC pipe — the socket end is sized to accept standard PVC pipe of the corresponding nominal size. For example, a 25mm ID valve fits standard ½\" or ¾\" nominal PVC pipe depending on your regional standard. Measure your existing pipe OD and cross-reference with your local PVC pipe schedule before ordering.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eCan this valve be installed vertically as well as horizontally?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eFlap check valves can generally be installed horizontally or vertically with upward flow. Vertical installation with downward flow is not recommended for gravity-flap designs, as the flap may not seal reliably under low back-pressure. Check the flow-direction arrow moulded on the valve body before fitting.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eIs this valve suitable for hot water or chemical service?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eNo. Rigid PVC is rated for cold-water service only — typically up to 45°C (113°F). It is not suitable for hot water, steam, or aggressive chemical media. For hot water applications, consider CPVC or brass check valves. For chemical compatibility, consult a PVC chemical resistance chart for your specific fluid.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWhat adhesive should I use to join this valve to my pipe?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eUse a standard PVC solvent cement (ASTM D2564 or equivalent) with a PVC primer\/cleaner. Apply primer to both the pipe end and the socket interior, then apply cement and push the pipe firmly into the socket with a quarter-turn. Allow the joint to cure per the cement manufacturer's instructions before pressurising the line.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWhat is the difference between the Dark Grey and Transparent versions?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eBoth versions are functionally identical. The Transparent body allows you to visually inspect the flap position and confirm flow direction without cutting into the line — useful for troubleshooting or monitoring intermittent pump systems. The Dark Grey version is the standard choice for concealed or outdoor installations where UV exposure or aesthetics are a consideration.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eHow do I know if the valve is working correctly after installation?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eWith the Transparent variant, you can observe the flap opening during forward flow and closing when the pump stops. For Dark Grey variants, confirm correct operation by shutting off the pump and checking that no backflow occurs at the upstream side. A slight click or thud when the pump stops is normal — it indicates the flap has closed. Persistent backflow suggests the flap seat may have debris; flush the line and inspect.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eCan I use this valve in an irrigation or pond pump system?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\u003cp\u003eYes. PVC non-return flap check valves are widely used on pond pump outlets, drip irrigation mains, and sprinkler system return lines to prevent siphoning and backflow when the pump cycles off. Ensure the valve ID matches your irrigation pipe size and that the working pressure does not exceed the valve's rated pressure for your chosen size.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"hdiy-cta\"\u003e\n🛒 Select your Inner Diameter and Colour above, then add to cart.\n\u003c\/div\u003e\n\n\u003c\/div\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Which inner diameter should I choose for my pipe?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Match the ID of the valve to the outer diameter (OD) of your PVC pipe. The socket end is sized to accept standard PVC pipe of the corresponding nominal size. Measure your existing pipe OD and cross-reference with your local PVC pipe schedule before ordering.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can this valve be installed vertically as well as horizontally?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Flap check valves can generally be installed horizontally or vertically with upward flow. Vertical installation with downward flow is not recommended. Check the flow-direction arrow moulded on the valve body before fitting.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Is this valve suitable for hot water or chemical service?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"No. Rigid PVC is rated for cold-water service only, typically up to 45°C (113°F). It is not suitable for hot water, steam, or aggressive chemical media.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What adhesive should I use to join this valve to my pipe?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Use a standard PVC solvent cement (ASTM D2564 or equivalent) with a PVC primer\/cleaner. Apply primer to both the pipe end and the socket interior, then apply cement and push the pipe firmly into the socket with a quarter-turn.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is the difference between the Dark Grey and Transparent versions?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Both versions are functionally identical. The Transparent body allows visual inspection of the flap position and flow direction. The Dark Grey version is the standard choice for concealed or outdoor installations.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"How do I know if the valve is working correctly after installation?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"With the Transparent variant, observe the flap opening during forward flow and closing when the pump stops. For Dark Grey variants, confirm no backflow occurs at the upstream side after shutting off the pump.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I use this valve in an irrigation or pond pump system?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes. PVC non-return flap check valves are widely used on pond pump outlets, drip irrigation mains, and sprinkler system return lines to prevent siphoning and backflow when the pump cycles off.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e","brand":"HomeDIYer","offers":[{"title":"20mm \/ Dark Grey","offer_id":52331616665874,"sku":"GLFBWJJGLBZSJ020530x1","price":23.54,"currency_code":"USD","in_stock":true},{"title":"25mm \/ Dark Grey","offer_id":52331616698642,"sku":"GLFBWJJGLBZSJ020531x1","price":30.06,"currency_code":"USD","in_stock":true},{"title":"32mm \/ Dark Grey","offer_id":52331616731410,"sku":"GLFBWJJGLBZSJ020532x1","price":38.46,"currency_code":"USD","in_stock":true},{"title":"40mm \/ Dark Grey","offer_id":52331616764178,"sku":"GLFBWJJGLBZSJ020533x1","price":49.8,"currency_code":"USD","in_stock":true},{"title":"50mm \/ Dark Grey","offer_id":52331616796946,"sku":"GLFBWJJGLBZSJ020534x1","price":55.43,"currency_code":"USD","in_stock":true},{"title":"63mm \/ Dark Grey","offer_id":52331616829714,"sku":"GLFBWJJGLBZSJ020535x1","price":71.4,"currency_code":"USD","in_stock":true},{"title":"20mm \/ Transparent","offer_id":52331616862482,"sku":"GLFBWJJGLBZSJ020536x1","price":50.1,"currency_code":"USD","in_stock":true},{"title":"25mm \/ Transparent","offer_id":52331616895250,"sku":"GLFBWJJGLBZSJ020537x1","price":63.76,"currency_code":"USD","in_stock":true},{"title":"32mm \/ Transparent","offer_id":52331616928018,"sku":"GLFBWJJGLBZSJ020538x1","price":80.48,"currency_code":"USD","in_stock":true},{"title":"40mm \/ Transparent","offer_id":52331616960786,"sku":"GLFBWJJGLBZSJ020539x1","price":108.27,"currency_code":"USD","in_stock":true},{"title":"50mm \/ Transparent","offer_id":52331616993554,"sku":"GLFBWJJGLBZSJ020540x1","price":131.21,"currency_code":"USD","in_stock":true},{"title":"63mm \/ Transparent","offer_id":52331617026322,"sku":"GLFBWJJGLBZSJ020541x1","price":168.54,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/8936\/1682\/files\/Picture1of14_6ee95327-96e5-418c-8497-9f48793a028c.jpg?v=1781924850","url":"https:\/\/homediyer.com\/de\/products\/pvc-one-way-non-return-flap-check-valve-id-20-25-32-40-50-63mm","provider":"HomeDIYer","version":"1.0","type":"link"}