{"product_id":"543-020","title":"543-020","description":"Ensure your heating system operates safely and efficiently with this premium 3-inch high limit control switch. Designed as a critical safety component for forced-air gas furnaces and HVAC units, this switch monitors the internal temperature of the heat exchanger to prevent overheating. If the furnace temperature exceeds the safe threshold of 140°F, the switch automatically breaks the electrical circuit to shut down the burners, protecting your equipment from damage and ensuring home safety. Once the internal temperature drops by 30°F, the switch resets to allow for normal operation. This high limit switch is an essential replacement part for troubleshooting furnace short-cycling, blower motor issues, or thermal safety trips in residential heating systems.\u003cbr\u003e\nType: High Limit Control Switch\u003cbr\u003e\nSize: 3-inch probe\u003cbr\u003e\nDimensions: 3 in (insertion depth)\u003cbr\u003e\nApplication: Used primarily in gas furnaces and forced-air heating systems as a primary safety limit to prevent heat exchanger damage.\u003cbr\u003e\nSpecifications: Opening Temperature: 140°F; Differential\/Closing Temperature: 30°F below setpoint; Normally Closed (NC) circuit; Automatic reset functionality.","brand":"BCFurnace","offers":[{"title":"3\" HIGH LIMIT SWITCH L140-30F \/ 543-020","offer_id":47251507446045,"sku":null,"price":68.83,"currency_code":"CAD","in_stock":true},{"title":"3\" HIGH LIMIT SWITCH L140-30F \/ 29M74","offer_id":47251507478813,"sku":null,"price":68.83,"currency_code":"CAD","in_stock":true},{"title":"3\" HIGH LIMIT SWITCH L140-30F \/ 29M7401","offer_id":47251507511581,"sku":null,"price":68.83,"currency_code":"CAD","in_stock":true},{"title":"3\" HIGH LIMIT SWITCH L140-30F \/ L140-30F..","offer_id":47251507544349,"sku":null,"price":68.83,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0836\/7298\/9981\/files\/94e4e8e3738b4928921d762ebbadb3ab.webp?v=1773958844","url":"https:\/\/bcfurnace.myshopify.com\/products\/543-020","provider":"BCFurnace","version":"1.0","type":"link"}