{"product_id":"oem-lennox-adjustable-fan-limit-thermostat-175-215-f-27p99","title":"OEM Lennox Adjustable Fan\/Limit Thermostat 175-215°F — 27P99","description":"\u003cp\u003eThe Lennox \u003cstrong\u003e27P99\u003c\/strong\u003e is a genuine OEM adjustable fan and limit thermostat with a 175–215°F temperature range and a 40°F differential. It performs two jobs in your furnace: it energizes the blower once the heat exchanger warms up, and it acts as a high-limit safety switch that shuts the burners down if the plenum overheats. This dual function keeps your Lennox furnace running efficiently while protecting the heat exchanger from thermal damage.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCommon failure symptoms:\u003c\/strong\u003e When the \u003cstrong\u003e27P99\u003c\/strong\u003e fails or drifts out of calibration, you may notice the blower short-cycling, the fan running constantly, no warm air delivery, or the furnace tripping on the limit and locking out. A worn or corroded bimetal element frequently causes these issues.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy OEM matters:\u003c\/strong\u003e Lennox furnaces are engineered around precise fan-on\/fan-off and limit setpoints. Using the factory-spec \u003cstrong\u003e27P99\u003c\/strong\u003e guarantees the correct temperature calibration, terminal layout, and probe length for a safe, direct fit — no field modification or guesswork. Generic substitutes can trip early, delay blower engagement, or fail to protect the heat exchanger. Insist on genuine OEM to preserve your equipment's safety rating and warranty.\u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":63081078686067,"sku":"LNX-27P99","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-27P99.jpg?v=1783759299","url":"https:\/\/nationalhvacparts.com\/products\/oem-lennox-adjustable-fan-limit-thermostat-175-215-f-27p99","provider":"National HVAC Parts","version":"1.0","type":"link"}