{"product_id":"pentair_25022-0224s","title":"Pentair Large Cartridge | System 3 | 25022-0224S","description":"\u003cp\u003eThe Pentair Large Cartridge Filter Element (25022-0224S) is the OEM replacement 21 in. outer filter cartridge for the Sta-Rite System 3 Modular Media filter, model S7M400.\u003c\/p\u003e\n\u003cp\u003eThis cartridge is the outer filtration element in the System 3's two-piece tank design. It captures debris as pool water passes through its shallow-pleat media before the filtered water returns to circulation. The shallow pleat geometry maximizes surface area for dirt-holding capacity while allowing quick rinse-downs during routine service, without needing to open or disturb the tank housing itself.\u003c\/p\u003e\n\u003cp\u003eThis is the larger, outer cartridge for the S7M400.  For the matching smaller, inner cartridge, see part number \u003ca href=\"https:\/\/poolaroo.com\/products\/pentair_25021-0223s\"\u003e\u003cstrong\u003e25021-0223S\u003c\/strong\u003e\u003c\/a\u003e\u003ca href=\"https:\/\/poolaroo.com\/products\/pentair_25021-0200s\"\u003e\u003cstrong\u003e\u003c\/strong\u003e\u003c\/a\u003e.  Replace both to complete your filter service.\u003c\/p\u003e\n\u003cp\u003eFor a combo back of both filter cartridges, see the combo pack: \u003ca href=\"https:\/\/poolaroo.com\/products\/pentair_170146\"\u003e\u003cstrong\u003e170146\u003c\/strong\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; margin: 20px 0; border: 1px solid #ccc;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003ePentair Part Number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e25022-0224S\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: white;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003ePart Name\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eLarge Cartridge (Outer Filter Element)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eSize\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e21 in.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: white;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eQuantity Included\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eEach\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eFits Into\u003c\/h3\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; margin: 20px 0; border: 1px solid #ccc;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eBrand\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eEquipment Line\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eModel \/ Part Number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003eNotes\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: white;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003ePentair\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eSystem 3\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eS7M400\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e21 in. Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cem\u003eCompatibility is based on Pentair parts documentation and available OEM records. This is not an exhaustive list. For certainty, verify the part number in your equipment's manual or on the original part itself before ordering.\u003c\/em\u003e\u003c\/p\u003e\n\u003ch3\u003ePoolaroo Pro Tip\u003c\/h3\u003e\n\u003cp\u003eBecause the System 3 tank's housing gives you direct access without disassembly, rinse this cartridge with a garden hose every time you clean your filter rather than waiting for a full service cycle. Regular rinsing preserves the pleat spacing and keeps flow rates consistent, which extends the interval between deep-cleaning or replacement.\u003c\/p\u003e\n\u003c!-- wft:processed:manual:2026-08-24 --\u003e","brand":"Pentair","offers":[{"title":"Default Title","offer_id":54309090361619,"sku":"25022-0224S","price":728.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0920\/0687\/5411\/files\/PEN250220224S_0.jpg?v=1781714184","url":"https:\/\/poolaroo.com\/products\/pentair_25022-0224s","provider":"Poolaroo","version":"1.0","type":"link"}