{"product_id":"n9378-1","title":"Baxi Expansion Vessel 7L 7683801","description":"\u003ch1\u003e\u003cspan\u003eBaxi Boiler Expansion Vessel 7L 7683801\u003c\/span\u003e\u003c\/h1\u003e\n\u003ch2\u003e\u003cspan\u003eProduct Overview\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eThe \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eBaxi Boiler Expansion Vessel 7L (Part Number: 7683801)\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e is a replacement expansion vessel assembly designed for use within selected Baxi heating systems.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eThe expansion vessel is an important component of a sealed heating system. It accommodates the increase in water volume that occurs as the heating system heats up, helping to control pressure changes and maintain stable system operation.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eThe \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e7683801\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e is a \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e7-litre expansion vessel assembly\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e and is supplied as a complete vessel assembly rather than a repair kit. Baxi documentation also identifies 7683801 as an expansion vessel spare part.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eℹ️ \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eProduct Condition Options:\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eThis part may be available in \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eNew or Refurbished\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e condition. Please check the available options from the dropdown menu.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eTechnical Insight \u0026amp; Common Failure Symptoms\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eAn expansion vessel contains an internal diaphragm separating the heating system water from a pressurised air or gas chamber. As the system water heats and expands, the vessel provides space for this expansion, helping to prevent excessive increases in system pressure.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eOver time, an expansion vessel may lose its charge or the internal diaphragm may deteriorate, reducing its ability to manage pressure correctly.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eTypical symptoms associated with an expansion vessel requiring replacement or servicing include:\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan\u003eBoiler pressure rising significantly when the heating is operating\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eFrequent pressure loss from the heating system\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eFrequent need to repressurise the boiler\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003ePressure relief valve discharging water\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eLarge fluctuations in system pressure\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eExpansion vessel losing its ability to absorb thermal expansion\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eA correctly sized and functioning expansion vessel helps maintain stable pressure and reliable operation of the sealed heating system.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eTechnical Specifications\u003c\/span\u003e\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eManufacturer:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Baxi\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eManufacturer Part Number (MPN):\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e 7683801\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eType:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e Expansion Vessel Assembly\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003eCapacity:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e 7 Litres\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003cspan\u003ePack Quantity:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e 1\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eThe 7-litre capacity and part number 7683801 are confirmed by Baxi parts documentation and UK boiler-spares suppliers.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eCompatibility\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003eThis part is designed for selected models within the \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eBaxi\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e range and is also used under the same manufacturer part number in selected \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003eMain and Potterton\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e applications.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"isSelectedEnd\"\u003e\u003cspan\u003ePlease strictly verify the manufacturer part number \u003c\/span\u003e\u003cstrong\u003e\u003cspan\u003e7683801\u003c\/span\u003e\u003c\/strong\u003e\u003cspan\u003e against your boiler's technical manual, exploded parts diagram, or existing expansion vessel before ordering to guarantee correct fitment.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch2\u003e\u003cspan\u003eSafety Advice\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp\u003e\u003cem\u003eExpansion vessels form part of a sealed heating system and operate under pressure. Installation, replacement, pressure adjustment, and boiler servicing should only be carried out by a suitably qualified heating engineer in accordance with the manufacturer's instructions and applicable UK safety regulations.\u003c\/em\u003e\u003c\/p\u003e","brand":"National Boiler Spares","offers":[{"title":"New \/ Compatible","offer_id":44400015442023,"sku":"N9378","price":70.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0615\/0923\/8887\/files\/N9378_39fcf27f-3443-4eca-a1bc-a520b17b0679.webp?v=1786438497","url":"https:\/\/nationalboilerspares.co.uk\/products\/n9378-1","provider":"National Boiler Spares","version":"1.0","type":"link"}