{"product_id":"mcdonnell-miller-113550-fs1-j-liquid-flow-switch","title":"McDonnell \u0026 Miller 113550 FS1-J Liquid Flow Switch","description":"\u003cp\u003eMaintain optimal protection for your hydronic systems with the \u003cstrong\u003eMcDonnell \u0026amp; Miller 113550\u003c\/strong\u003e, also known as the \u003cstrong\u003eFS1-J\u003c\/strong\u003e flow switch. This critical safety component is designed to actuate a signal in response to fluid flow, helping to prevent equipment damage in heating and cooling circuits by monitoring movement within the piping.\u003c\/p\u003e\u003cp\u003eThe unit utilizes a precision-engineered paddle mechanism that moves with the velocity of the fluid, mechanically triggering an internal switch when flow conditions deviate from established parameters. This simple yet rugged design ensures consistent response times and long-term durability in demanding HVAC environments.\u003c\/p\u003e\u003ch4\u003eKey System Performance Baselines:\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision Sensing:\u003c\/strong\u003e Reliable detection of fluid movement to protect critical pumping and heating assets.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRugged Build:\u003c\/strong\u003e Engineered for industrial and commercial longevity in hydronic applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeamless Integration:\u003c\/strong\u003e Compact design that allows for straightforward installation in standard piping configurations.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e⚠️ \u003cstrong\u003eApplication Profile:\u003c\/strong\u003e Primarily used in commercial chillers, residential boiler systems, liquid transfer lines, and booster pump monitoring to prevent dry-running or flow-loss conditions.\u003c\/p\u003e","brand":"McDonnell \u0026 Miller","offers":[{"title":"Default Title","offer_id":43123964641374,"sku":"113550","price":332.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0663\/7151\/8558\/files\/113550_image_2c929670-aeab-43fd-bd43-c6d2dd310a38.png?v=1786027120","url":"https:\/\/nationalboilersupply.com\/products\/mcdonnell-miller-113550-fs1-j-liquid-flow-switch","provider":"National Boiler Supply","version":"1.0","type":"link"}