{"product_id":"mcdonnell-miller-181625-250-3-4-75-asme-relief-valve","title":"McDonnell \u0026 Miller 181625 250-3\/4-75 ASME Relief Valve","description":"\u003cp\u003eMaintain optimal safety and pressure regulation in your boiler system with the \u003cstrong\u003e181625\u003c\/strong\u003e McDonnell \u0026amp; Miller relief valve. This essential component, designated as model \u003cstrong\u003e250-3\/4-75\u003c\/strong\u003e, is designed to protect hydronic heating equipment by automatically discharging fluid if internal system pressure exceeds the factory set threshold.\u003c\/p\u003e\u003cp\u003eThis relief valve operates using a high-precision spring-loaded mechanism that ensures tight sealing during normal operation while providing rapid, reliable response during an over-pressurization event. Engineered for durability, the valve body and internal seat are constructed to resist corrosion and mineral buildup, ensuring consistent performance over the long lifecycle of your heating installation.\u003c\/p\u003e\u003ch4\u003eKey System Performance Baselines:\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePressure Setting:\u003c\/strong\u003e Factory calibrated to open at 75 PSI.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnection Type:\u003c\/strong\u003e Standard 3\/4\" NPT inlet and outlet for easy installation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eASME Compliance:\u003c\/strong\u003e Rated to meet rigorous industry standards for boiler safety.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEfficient Flow:\u003c\/strong\u003e Optimized discharge capacity to safely mitigate sudden pressure spikes.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e⚠️ \u003cstrong\u003eApplication Profile:\u003c\/strong\u003e Primarily designed for use in hot water boilers, closed-loop hydronic heating systems, and domestic hot water supply tanks requiring code-compliant pressure relief.\u003c\/p\u003e","brand":"McDonnell \u0026 Miller","offers":[{"title":"Default Title","offer_id":43127326769246,"sku":"181625","price":184.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0663\/7151\/8558\/files\/181625_image_b105c5cd-ab40-4e87-8d45-c75735549a3e.png?v=1786050419","url":"https:\/\/nationalboilersupply.com\/products\/mcdonnell-miller-181625-250-3-4-75-asme-relief-valve","provider":"National Boiler Supply","version":"1.0","type":"link"}