{"product_id":"unicelreplacementfiltercartridge75sfrainbowrtl75c4975unfc4975","title":"Unicel Replacement Filter Cartridge 75 sf Rainbow RTL-75 | C-4975","description":"\u003cdiv\u003e\n\u003ch2\u003eUnicel C-4975 – 75 sq ft Replacement Cartridge\u003c\/h2\u003e\n\u003ch3\u003eProduct Overview\u003c\/h3\u003e\n\u003cp\u003eThe Unicel C-4975 is a high-quality replacement cartridge filter designed for spa and pool systems. With approximately 75 square feet of pleated polyester media, it offers excellent debris capture and flow performance for compatible filter tanks.\u003c\/p\u003e\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e75 sq ft of filtration area to handle heavier loads and extend cleaning intervals.\u003c\/li\u003e\n\u003cli\u003eDurable polyester media combined with a reinforced core and end caps for repeated use and rinsing.\u003c\/li\u003e\n\u003cli\u003ePrecision dimensions: Outside diameter ~4-15\/16\", length ~20-1\/8\", and inner diameter ~2-1\/8\" (open both ends).\u003c\/li\u003e\n\u003cli\u003eDirect replacement for a variety of cartridge filter models from several manufacturers.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003ePart Number: C-4975\u003c\/li\u003e\n\u003cli\u003eSquare Feet: ~75 sq ft\u003c\/li\u003e\n\u003cli\u003eOutside Diameter: ~4-15\/16” (~125.4 mm)\u003c\/li\u003e\n\u003cli\u003eLength: ~20-1\/8” (~511 mm)\u003c\/li\u003e\n\u003cli\u003eInner Diameter (both ends): ~2-1\/8” (~54 mm), open end style\u003c\/li\u003e\n\u003cli\u003ePleat Count: ~210 pleats\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eApplications \u0026amp; Compatibility\u003c\/h3\u003e\n\u003cp\u003eThis cartridge is suitable for use in many spa and pool systems where the original cartridge specified a 4-15\/16\" diameter and 20-1\/8” length with open ends. Its large filtration area and reliable construction make it a good choice for replacing worn cartridges in commercial or high-usage residential systems.\u003c\/p\u003e\n\u003ch3\u003eInstallation Instructions\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eTurn off the pump and relieve pressure from the filter system before opening the tank.\u003c\/li\u003e\n\u003cli\u003eRemove the old cartridge, clean the filter tank interior and inspect for signs of wear or damage.\u003c\/li\u003e\n\u003cli\u003eInsert the new C-4975 cartridge, ensuring it is correctly seated and the open ends are properly aligned with the filter tank ports.\u003c\/li\u003e\n\u003cli\u003eReassemble the filter tank, restore power and pump operation, then monitor pressure and flow to confirm proper installation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eTroubleshooting \u0026amp; Tips\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh pressure on start-up:\u003c\/strong\u003e Verify that the cartridge pleats are fully expanded and not compressed or bent.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReduced flow:\u003c\/strong\u003e Check for debris build-up in pleats; rinse cartridge thoroughly or consider replacement if media is damaged.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLeaks or bypass in tank:\u003c\/strong\u003e Ensure the cartridge only fits one orientation (open ends match tank ports) and that the tank lid or closure is sealed correctly.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eMaintenance Tip\u003c\/h3\u003e\n\u003cp\u003eFor best results, rinse the cartridge monthly (or more often in heavy use or high debris systems) and schedule replacement every 12-18 months or when the pleats show a permanent discoloration or damage. Keeping the cartridge clean and replacing at the appropriate interval helps maintain water clarity, system efficiency, and prolongs pump and heater life.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Unicel","offers":[{"title":"Default Title","offer_id":46797824360623,"sku":"C-4975","price":49.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/6415\/2239\/files\/unicel-replacement-filter-cartridge-75-sf-rainbow-rtl-75-c-4975-cartridges-4449674.jpg?v=1777067774","url":"https:\/\/freshized.com\/products\/unicelreplacementfiltercartridge75sfrainbowrtl75c4975unfc4975","provider":"Freshized","version":"1.0","type":"link"}