{"product_id":"chlorine-control-valve","title":"Pentair R172022 Old Style Chlorine Control Valve","description":"\u003cp\u003eThe Pentair R172022 is the old style chlorine control valve for the Model 300, 302, 300-19 and 300-29 automatic chemical feeders.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat it controls\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eAn off line tablet feeder works by diverting a small share of the return flow through the chlorinator body, where it dissolves tablets before rejoining the line. The control valve is what sets that share. Turn it up and the feeder dissolves faster, turn it down and output drops. It is the only real adjustment on the feeder.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy they fail\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe valve lives in the most chemically aggressive spot in the whole system. Undissolved tablet residue and calcium build on the stem until the knob spins without doing anything, or the valve sticks wide open and the pool runs hot on chlorine. Replacing the valve restores the adjustment.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eBefore you order\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThis is specifically the old style valve. Check R172022 against your feeder so you get the version that matches.\u003c\/p\u003e","brand":"Pentair","offers":[{"title":"Default Title","offer_id":48627979354324,"sku":"RAI-451-4015","price":34.07,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0801\/9568\/2516\/files\/default_08497678-20ce-4689-a83d-289f91156a93.png?v=1788732232","url":"https:\/\/www.activepoolsupply.com\/products\/chlorine-control-valve","provider":"Active Pool Supply","version":"1.0","type":"link"}