{"product_id":"watts-4425-18","title":"Watts M116FM 300-4 Relief Valve, Ductile Iron, Flanged","description":"\u003cp\u003eThe Watts M116FM 300-4 is a 4\" globe-pattern pilot-operated pressure relief \/ sustaining \/ backpressure control valve with Flanged connections. It features a ductile iron body. Rated to 300 psi.\u003c\/p\u003e\u003cp\u003eThis class 300 4 inch relief valve meets all requirements for UL listed, FM Approved fire protection service. It automatically maintains a constant pressure in the fire protection system by relieving excess pressure. The pressure relief control is normally closed, held closed by an adjustable spring setting to maintain a constant inlet pressure to the main valve.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003ePressure relief control valve\u003c\/li\u003e\n\u003cli\u003eClass 300 flanged\u003c\/li\u003e\n\u003cli\u003e300 psig rated\u003c\/li\u003e\n\u003cli\u003eCopper tubing\/brass fittings\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCommon Questions\u003c\/strong\u003e\u003c\/p\u003e\u003cdl\u003e\n\u003cdt\u003e\u003cstrong\u003eWhat is the maximum working pressure?\u003c\/strong\u003e\u003c\/dt\u003e\n\u003cdd\u003eThis unit is built as 300# Flanged and is rated to 300 psi. End connection sets the ceiling on this platform, and 150# and 300# bodies are not interchangeable — confirm the class matches your flange drilling before ordering.\u003c\/dd\u003e\n\u003cdt\u003e\u003cstrong\u003eIs this valve UL Listed and FM Approved for fire protection?\u003c\/strong\u003e\u003c\/dt\u003e\n\u003cdd\u003eYes — this model carries the UL listing and FM approval required for fire-protection service. Non-listed control valves cannot be substituted on a fire job even when the body and pilot are otherwise identical.\u003c\/dd\u003e\n\u003c\/dl\u003e\u003cp\u003e\u003cstrong\u003eSpecifications\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e Relief\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 4\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInlet Size:\u003c\/strong\u003e 4\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOutlet Size:\u003c\/strong\u003e 4\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection:\u003c\/strong\u003e Flanged\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBody Material:\u003c\/strong\u003e Ductile Iron\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePressure Class:\u003c\/strong\u003e Class 300\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Pressure (psi):\u003c\/strong\u003e 300\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication:\u003c\/strong\u003e Fire Protection\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperation:\u003c\/strong\u003e Pilot-Operated Diaphragm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCountry of Origin:\u003c\/strong\u003e United States\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 1 Year Limited\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMPN:\u003c\/strong\u003e M116FM 300-4\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLead-Free:\u003c\/strong\u003e No\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eItem Type:\u003c\/strong\u003e Valve\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eControl Function:\u003c\/strong\u003e Pressure Relief \/ Sustaining \/ Backpressure\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eValve Platform:\u003c\/strong\u003e Mustang (M-Series)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBody Pattern:\u003c\/strong\u003e Globe\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEnd Connection \/ Pressure Class:\u003c\/strong\u003e 300# Flanged\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoating:\u003c\/strong\u003e Fusion-Bonded Epoxy\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUL Listed \/ FM Approved:\u003c\/strong\u003e Yes\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Watts","offers":[{"title":"Default Title","offer_id":54935011688747,"sku":"4425-18","price":11024.81,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0277\/3168\/9577\/files\/d8d47c725869ea13d2364de5f08a168708f2d6ca_b93ce36f-602e-4d68-be80-8b55fbe5c791.jpg?v=1785981022","url":"https:\/\/citysupplygroup.com\/products\/watts-4425-18","provider":"City Supply","version":"1.0","type":"link"}