{"product_id":"vaillant-eco-tec-plus-pro-main-heat-exchanger-thermal-fuse-sensor-f76-fault-2","title":"Vaillant Eco Tec Plus \u0026 Pro Main Heat Exchanger Thermal Fuse Sensor (F76 Fault)","description":"\u003ch3 data-section-id=\"9hbb1c\" data-start=\"305\" data-end=\"332\"\u003e📌 What these parts are\u003c\/h3\u003e\n\u003cul data-start=\"333\" data-end=\"677\"\u003e\n\u003cli data-section-id=\"1vpso2m\" data-start=\"333\" data-end=\"677\"\u003e\n\u003cstrong data-start=\"335\" data-end=\"377\"\u003eF76 Thermal Fuse \/ Thermal Fuse Sensor\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003e— a safety device fitted on\/near the\u003cspan\u003e \u003c\/span\u003e\u003cstrong data-start=\"415\" data-end=\"438\"\u003emain heat exchanger\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eon\u003cspan\u003e \u003c\/span\u003e\u003cspan class=\"hover:entity-accent entity-underline inline cursor-pointer align-baseline\"\u003eVaillant Thermal Fuse Sensor Ecotec Plus Main Heat Exchanger\u003c\/span\u003e\u003cspan\u003e \u003c\/span\u003eand similar parts. It\u003cspan\u003e \u003c\/span\u003e\u003cstrong data-start=\"502\" data-end=\"525\"\u003edetects overheating\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eand will trigger an\u003cspan\u003e \u003c\/span\u003e\u003cstrong data-start=\"546\" data-end=\"564\"\u003eF76 fault code\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eif temperatures exceed safe limits to protect the boiler’s heat exchanger.\u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-section-id=\"xs59kv\" data-start=\"679\" data-end=\"706\"\u003e🛠️ About the F76 error\u003c\/h3\u003e\n\u003cul data-start=\"707\" data-end=\"1460\"\u003e\n\u003cli data-section-id=\"1uqn01n\" data-start=\"707\" data-end=\"957\"\u003eThe\u003cspan\u003e \u003c\/span\u003e\u003cstrong data-start=\"713\" data-end=\"731\"\u003eF76 fault code\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003emeans the\u003cspan\u003e \u003c\/span\u003e\u003cstrong data-start=\"742\" data-end=\"819\"\u003eoverheating protection on the primary (main) heat exchanger has responded\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003e— usually because the thermal fuse has gone open circuit or the heat exchanger has been overheated.\u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"8pa49b\" data-start=\"958\" data-end=\"1218\"\u003eSome thermal fuse sensors are sold separately as a\u003cspan\u003e \u003c\/span\u003e\u003cstrong data-start=\"1011\" data-end=\"1031\"\u003ereplacement part\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003efor the wiring\/connector component, but in many cases the\u003cspan\u003e \u003c\/span\u003e\u003cstrong data-start=\"1090\" data-end=\"1128\"\u003ethermal fuse itself can’t be reset\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eif it has actually blown inside the heat exchanger.\u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli data-section-id=\"12etatk\" data-start=\"1219\" data-end=\"1460\"\u003eIf the fuse has blown due to overheating (not just a wiring defect), this\u003cspan\u003e \u003c\/span\u003e\u003cstrong data-start=\"1295\" data-end=\"1336\"\u003eoften indicates heat exchanger damage\u003c\/strong\u003e, and replacing the heat exchanger — or sometimes the whole boiler — may be necessary.\u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-section-id=\"doa09h\" data-start=\"1462\" data-end=\"1489\"\u003e📍 Common compatibility\u003c\/h3\u003e\n\u003cp data-start=\"1490\" data-end=\"1557\"\u003eThese thermal fuse sensors are generally listed as compatible with:\u003c\/p\u003e\n\u003cul data-start=\"1558\" data-end=\"1867\"\u003e\n\u003cli data-section-id=\"17v1j1c\" data-start=\"1558\" data-end=\"1594\"\u003e\n\u003cstrong data-start=\"1560\" data-end=\"1584\"\u003eVaillant ecoTEC Plus\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eboilers\u003c\/li\u003e\n\u003cli data-section-id=\"17cmt19\" data-start=\"1595\" data-end=\"1867\"\u003e\n\u003cstrong data-start=\"1597\" data-end=\"1620\"\u003eVaillant ecoTEC Pro\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eboilers\u003cbr data-start=\"1628\" data-end=\"1631\"\u003e(Other related ranges use similar F76 components)\u003cspan class=\"\" data-state=\"closed\"\u003e\u003c\/span\u003e\u003cbr data-start=\"1718\" data-end=\"1721\"\u003eHowever, compatibility can vary by model year and specific heat exchanger design, so always check the boiler’s GC \/ model reference before buying.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 data-section-id=\"9foi78\" data-start=\"1869\" data-end=\"1879\"\u003e⚠️ Tip\u003c\/h3\u003e\n\u003cp data-start=\"1880\" data-end=\"1932\"\u003eF76 faults are relatively serious — often caused by:\u003c\/p\u003e\n\u003cul data-start=\"1933\" data-end=\"2211\"\u003e\n\u003cli data-section-id=\"1k3msy2\" data-start=\"1933\" data-end=\"1982\"\u003eBlocked system or poor water flow (overheating)\u003c\/li\u003e\n\u003cli data-section-id=\"xfo5v\" data-start=\"1983\" data-end=\"2020\"\u003eFaulty wiring harness to the sensor\u003c\/li\u003e\n\u003cli data-section-id=\"uu9euc\" data-start=\"2021\" data-end=\"2211\"\u003eActual main heat exchanger overheating or damage\u003cbr data-start=\"2071\" data-end=\"2074\"\u003eA competent\u003cspan\u003e \u003c\/span\u003e\u003cstrong data-start=\"2086\" data-end=\"2107\"\u003eGas Safe engineer\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eshould diagnose the root cause before you fit a replacement part.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"VAILLANT","offers":[{"title":"Default Title","offer_id":57611508777334,"sku":null,"price":41.95,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0533\/0983\/3406\/files\/image7.jpg?v=1775291659","url":"https:\/\/star-boiler-spares.com\/en-ie\/products\/vaillant-eco-tec-plus-pro-main-heat-exchanger-thermal-fuse-sensor-f76-fault-2","provider":"Star boiler spares","version":"1.0","type":"link"}