{"product_id":"weil-mclain-381-800-878-pin-stem-assembly-eg-55-series-7-steam-boiler-without-vent-damper","title":"Weil-mclain 381-800-878 Pin Stem Assembly EG-55 Series 7 Steam Boiler Without Vent Damper","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe Weil-McLain 381-800-878 is a Pin Stem Assembly designed for use with EG-55 Series 7 residential cast iron steam boilers configured without a vent damper. This replacement part is a critical mechanical component that functions within the boiler's gas valve and control linkage system. It helps maintain proper alignment and actuation of internal components, ensuring the boiler operates safely and efficiently. Licensed HVAC technicians and heating contractors rely on OEM replacement parts like this to restore boiler systems to factory specifications. Using the correct pin stem assembly matters because a worn or damaged component can cause improper valve seating, erratic ignition sequencing, or system lockout conditions that interrupt heat delivery. The EG-55 Series 7 is a floor-mounted, gas-fired cast iron steam boiler rated at 200 MBH input and 167 MBH DOE heating capacity, with an AFUE rating of 82 percent. It uses electronic intermittent ignition and a stainless steel non-linting pilot burner. The boiler carries certifications from CSA, ASME, AHRI, and DOE, and is designed to meet strict residential heating codes. The 381-800-878 is manufactured specifically for units without a vent damper, so verifying the boiler configuration before ordering is essential. This part is intended for installation by a licensed and qualified heating professional in accordance with Weil-McLain installation instructions, local codes, and applicable industry standards. Warranty and technical support are handled exclusively through licensed contractors. Keeping original Weil-McLain parts in stock helps minimize system downtime during the heating season, which is especially important for steam boiler systems serving residential occupants. HVAC service technicians, boiler mechanics, and heating equipment wholesalers frequently source this type of OEM assembly for scheduled maintenance and emergency repair work.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eOEM pin stem assembly for Weil-McLain EG-55 Series 7 cast iron steam boilers\u003c\/li\u003e\n\u003cli\u003eDesigned for boiler configurations without vent damper — verify unit configuration before ordering\u003c\/li\u003e\n\u003cli\u003eSupports proper mechanical function of gas valve and control linkage components\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eProduct Highlights\u003c\/h4\u003e\u003cp\u003eThe Weil-McLain 381-800-878 Pin Stem Assembly is a direct OEM replacement for EG-55 Series 7 steam boilers without vent dampers, helping licensed heating professionals restore system performance to factory specifications quickly and reliably.\u003c\/p\u003e\u003ch3\u003eProduct Information\u003c\/h3\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: WEIL-MCLAIN\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 381-800-878\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatible Boiler Series\u003c\/strong\u003e: EG-55 Series 7\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVent Damper Configuration\u003c\/strong\u003e: Without Vent Damper\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBoiler Type\u003c\/strong\u003e: Steam\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFuel Type\u003c\/strong\u003e: Natural Gas\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAGA Input Rating\u003c\/strong\u003e: 200 MBH\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDOE Heating Capacity\u003c\/strong\u003e: 167 MBH\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNet IBR Rating\u003c\/strong\u003e: 125 MBH\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAFUE Rating\u003c\/strong\u003e: 82 Percent\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIgnition Type\u003c\/strong\u003e: Electronic Intermittent\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBurner Type\u003c\/strong\u003e: Stainless Steel, Non-Linting Pilot\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHeat Exchanger Material\u003c\/strong\u003e: Cast Iron\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting Type\u003c\/strong\u003e: Floor Mount\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVent Size\u003c\/strong\u003e: 7 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVenting Type\u003c\/strong\u003e: Automatic\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupply Connection\u003c\/strong\u003e: 3 inches Threaded\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReturn Connection\u003c\/strong\u003e: 2.5 inches Threaded\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGas Connection\u003c\/strong\u003e: 0.5 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePressure Rating\u003c\/strong\u003e: 50 PSI\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRelief Valve\u003c\/strong\u003e: 15 PSI ASME Relief Valve Supplied\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplicable Standards\u003c\/strong\u003e: CSA, ASME, AHRI, DOE\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty\u003c\/strong\u003e: 10 Year Limited (Heat Exchanger), 2 Year Limited (Other Parts)\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"WEIL-MCLAIN","offers":[{"title":"Default Title","offer_id":51121051631922,"sku":"381-800-878","price":6104.19,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/304884998.jpg?v=1777747044","url":"https:\/\/voomisupply.com\/products\/weil-mclain-381-800-878-pin-stem-assembly-eg-55-series-7-steam-boiler-without-vent-damper","provider":"Voomi Supply","version":"1.0","type":"link"}