{"product_id":"oem-lennox-pressure-switch-75m22","title":"OEM Lennox Pressure Switch — 75M22","description":"\u003cp\u003eThe genuine OEM Lennox \u003cstrong\u003e75M22\u003c\/strong\u003e pressure switch is a critical safety control that verifies proper airflow and venting in your furnace before allowing ignition. Connected to the draft inducer by a rubber hose, it senses negative pressure and closes its contacts only when adequate combustion airflow is confirmed. This factory-calibrated switch is set to the precise trip point required by your Lennox furnace, protecting against dangerous flue blockages and inadequate venting.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCommon failure symptoms:\u003c\/strong\u003e When the 75M22 fails or trips, the furnace typically will not light and often locks out on a fault code. Watch for the draft inducer running but no ignition, short cycling, a furnace that starts then shuts down, or blower-only operation with no heat. Cracked hoses, condensate blockage, or worn contacts are frequent causes.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy OEM matters:\u003c\/strong\u003e Pressure switches are calibrated to a specific \"inches of water column\" set point. A generic replacement with the wrong rating can nuisance-trip or, worse, allow the furnace to fire under unsafe venting conditions. The OEM Lennox \u003cstrong\u003e75M22\u003c\/strong\u003e delivers the exact factory calibration and connection fit your system was designed around, restoring safe, reliable furnace operation.\u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":63081095725427,"sku":"LNX-75M22","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-75M22.jpg?v=1783763076","url":"https:\/\/nationalhvacparts.com\/products\/oem-lennox-pressure-switch-75m22","provider":"National HVAC Parts","version":"1.0","type":"link"}