{"product_id":"oem-lennox-limit-switch-33j61","title":"OEM Lennox Limit Switch — 33J61","description":"\u003cp\u003eThe genuine OEM Lennox \u003cstrong\u003e33J61\u003c\/strong\u003e limit switch is a high-temperature safety control used in Lennox furnaces. It senses the temperature of the air passing over the heat exchanger and automatically shuts down the burner or heating element when temperatures exceed safe limits — a vital protection against cracked heat exchangers, overheated components, and fire hazards. Each \u003cstrong\u003e33J61\u003c\/strong\u003e is set to the exact trip temperature Lennox engineered for your model.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCommon failure symptoms\u003c\/strong\u003e include a furnace that short cycles, ignites then quickly shuts off, blows only cool air, runs the blower nonstop, or locks out with a limit-related fault code. A worn or drifted limit switch may trip early during normal operation or, worse, fail to open when the furnace genuinely overheats.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy OEM matters:\u003c\/strong\u003e limit switches are safety devices where calibration is everything. The Lennox \u003cstrong\u003e33J61\u003c\/strong\u003e matches the specified open and reset temperatures, terminal layout, and mounting for your furnace. Substituting a generic switch risks either nuisance lockouts or the loss of critical overheat protection. The factory part restores proper, safe operation exactly as designed.\u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":63081108930931,"sku":"LNX-33J61","price":19.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-limit-switch-snap-disc-LNX-33J61.jpg?v=1783762515","url":"https:\/\/nationalhvacparts.com\/products\/oem-lennox-limit-switch-33j61","provider":"National HVAC Parts","version":"1.0","type":"link"}