{"product_id":"oem-lennox-furnace-pressure-switch-49l91","title":"OEM Lennox Furnace Pressure Switch — 49L91","description":"\u003cp\u003eThe genuine OEM Lennox \u003cstrong\u003e49L91\u003c\/strong\u003e pressure switch is a combustion safety device that confirms adequate venting airflow before your furnace allows ignition. Sensing the vacuum produced by the draft inducer, it proves that exhaust gases are being properly drawn out of the heat exchanger and vented outdoors. Only when the correct pressure is detected does the switch close and permit the burners to light, making it an essential link in your Lennox furnace's safety chain.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCommon failure symptoms:\u003c\/strong\u003e The furnace tries to start but locks out, short-cycling, a control board displaying a pressure switch error, or the inducer running without ignition. Cracked hoses, a weak diaphragm, or corroded contacts inside the switch are typical causes of these no-heat conditions.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy OEM matters:\u003c\/strong\u003e Each Lennox furnace requires a pressure switch set to a precise trip point matched to its venting design. Installing a generic switch with an incorrect rating risks nuisance shutdowns or, worse, unsafe operation. The OEM \u003cstrong\u003e49L91\u003c\/strong\u003e delivers the exact factory calibration, wiring connector, and port configuration your Lennox system demands.\u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":63081104179571,"sku":"LNX-49L91","price":24.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-draft-inducer-LNX-49L91.jpg?v=1783761170","url":"https:\/\/nationalhvacparts.com\/products\/oem-lennox-furnace-pressure-switch-49l91","provider":"National HVAC Parts","version":"1.0","type":"link"}