{"product_id":"pentair-drain-vent-valve-o-ring-r172221","title":"Pentair O-Ring for Air Vent Valve | Dynamic Filter Series II \u0026 III RTL \/ RCF | R172221Z","description":"\u003cp\u003eThe Pentair O-Ring for Air Vent Valve (R172221Z) is the OEM replacement O-ring for the air vent valve on Pentair Dynamic Filter Series II \u0026amp; III cartridge filter equipment, as well as the compatible Chlorine\/Bromine Dispenser for RCF-RTL models.\u003c\/p\u003e\n\n\u003cp style=\"background-color: #fff3cd; border: 2px solid #FFEAA7; padding: 15px; border-radius: 5px; margin: 15px 0; color: #856404;\"\u003e\u003cstrong\u003eIMPORTANT: LUBRICATION REQUIRED — SOLD SEPARATELY\u003c\/strong\u003e\u003cbr\u003eAlways lubricate this O-ring with a silicone-based lubricant before installation. We carry the \u003ca href=\"https:\/\/poolaroo.com\/products\/pentairwaterpoolandspainc_r172351\" alt=\"Pentair R172351 Lifeguard Silicone Lubricant\"\u003ePentair R172351 Lifeguard Silicone Lubricant\u003c\/a\u003e — the OEM-matched product for Pentair equipment.\u003c\/p\u003e\n\n\u003cp\u003eThis O-ring seals the air vent valve on Pentair Dynamic Filter Series II \u0026amp; III housings. A compromised seal at the vent valve allows air to bypass the valve seat, disrupting proper air relief during filter startup and backwash cycles. Replacing this O-ring restores a proper airtight seal at the vent.\u003c\/p\u003e\n\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; margin: 20px 0; border: 1px solid #ccc;\"\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;\"\u003eR172221Z\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003e\u003cstrong\u003ePart Type\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eO-Ring for Air Vent Valve\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\u003eApplication\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eAir vent valve\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\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\/table\u003e\n\n\u003ch3\u003eFits Into\u003c\/h3\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; margin: 20px 0; border: 1px solid #ccc;\"\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\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003ePentair\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eDynamic Filter Series II \u0026amp; III RTL\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eRTL\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eTop Load In Line Cartridge Filter, 1-1\/2 in. \u0026amp; 2 in. High Flow\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003ePentair\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eDynamic Filter Series II \u0026amp; III RCF\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eRCF\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eTop Load In Line Cartridge Filter, 1-1\/2 in. \u0026amp; 2 in. High Flow\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003ePentair\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eChlorine\/Bromine Dispenser for RCF-RTL — Dynamic Filter Series\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eR172540\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eChlorine\/Bromine Dispenser for RCF-RTL\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f8f9fa;\"\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003ePentair\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eChlorine\/Bromine Dispenser F for RCF-RTL — Dynamic Filter Series\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eR172540F\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ccc; padding: 10px;\"\u003eChlorine\/Bromine Dispenser for RCF-RTL\u003c\/td\u003e\n\u003c\/tr\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\n\u003ch3\u003ePro Tip\u003c\/h3\u003e\n\u003cp\u003eBefore installing, clean the valve seat and O-ring groove thoroughly to remove any debris or residue from the old O-ring. Apply a thin, even coat of \u003ca href=\"https:\/\/poolaroo.com\/products\/pentairwaterpoolandspainc_r172351\" alt=\"Pentair R172351 Lifeguard Silicone Lubricant\"\u003ePentair R172351 Lifeguard Silicone Lubricant\u003c\/a\u003e to the O-ring before seating it — this prevents tearing during installation and ensures a proper seal. Never use petroleum-based lubricants, which degrade EPDM and similar elastomers.\u003c\/p\u003e\n\n\u003c!-- wft:processed:manual:2026-04-14 --\u003e","brand":"Pentair","offers":[{"title":"Default Title","offer_id":51774203461907,"sku":"R172221Z","price":5.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0920\/0687\/5411\/files\/PENR172221Z_0.jpg?v=1747704052","url":"https:\/\/poolaroo.com\/products\/pentair-drain-vent-valve-o-ring-r172221","provider":"Poolaroo","version":"1.0","type":"link"}