{"product_id":"h-series-pressure-switch","title":"Hayward H-Series Pressure Switch","description":"\u003cp\u003eThe Hayward FDXLWPS1930 is the pressure switch for Universal H-Series Low NOx heaters, covering models H150FD, H200FD, H250FD, H300FD, H350FD and H400FD. It is the genuine Hayward replacement.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat it does\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe switch is the heater safety that proves water is moving. Until it closes, the control will not allow the burner to light. That is deliberate: firing a heater with no flow through the exchanger is how exchangers get destroyed.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eThe symptom\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eA heater that runs the pump, shows no obvious fault at the filter and still refuses to fire is often sitting on an open pressure switch. Confirm real flow first, since low flow from a dirty filter or a closed valve produces the same lockout, then replace the switch if the plumbing side checks out.\u003c\/p\u003e","brand":"Hayward","offers":[{"title":"Default Title","offer_id":48628742029524,"sku":"HAY-151-0053","price":51.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0801\/9568\/2516\/files\/default_5a0893fe-21b4-4239-b1d9-e82546fafcf2.jpg?v=1788749525","url":"https:\/\/www.activepoolsupply.com\/products\/h-series-pressure-switch","provider":"Active Pool Supply","version":"1.0","type":"link"}