{"product_id":"orp-probe-heavy-duty","title":"Rola-Chem ORP Probe Heavy Duty","description":"\u003cp\u003eThe Rola-Chem 550136 is the heavy duty ORP probe with an 8 ft lead, made for Rola-Chem digital and analog controller systems.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat it measures\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eORP, oxidation reduction potential, is the reading a controller uses to judge how actively the sanitizer in the water is working. It is a better guide than raw chlorine concentration, because it reflects what the sanitizer is actually doing. The controller feeds chemical based on that number, so the probe is the piece the entire automated loop depends on.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhen to replace it\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eProbes are consumables. The sensing element slowly loses response, readings drift, and calibration stops holding. Once a probe will not stay calibrated after cleaning, it is done, and the controller is dosing on bad information until it is replaced.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eNote on the pair\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eORP and pH are read by separate probes. If your controller manages both, this listing covers the ORP side only; the matching 8 ft heavy duty pH probe is a separate Rola-Chem part.\u003c\/p\u003e","brand":"Rola-Chem","offers":[{"title":"Default Title","offer_id":48626478153940,"sku":"ROL-45-915","price":237.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0801\/9568\/2516\/files\/default_77d0a6a7-e2a2-4103-baae-625add9a7dd7.jpg?v=1788710690","url":"https:\/\/www.activepoolsupply.com\/products\/orp-probe-heavy-duty","provider":"Active Pool Supply","version":"1.0","type":"link"}