{"product_id":"oem-goodman-m4-primary-limit-switch-for-ams951155dxab-20162906","title":"OEM Goodman M4 Primary Limit Switch for AMS951155DXAB — 20162906","description":"\u003cp\u003eThe Goodman \u003cstrong\u003e20162906 M4 Primary Limit Switch\u003c\/strong\u003e is the genuine OEM high-limit control for the \u003cstrong\u003eAMS951155DXAB\u003c\/strong\u003e and matching Goodman\/Amana 95% single-stage furnaces. Mounted on the heat-exchanger bulkhead, the primary limit continuously monitors supply-air temperature and opens the gas\/blower circuit if the furnace runs too hot — protecting the heat exchanger from cracking due to restricted airflow or a stuck blower. The \"M4\" designation reflects its calibrated trip temperature for this furnace platform.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eType: Primary (main) high-limit switch — M4 series\u003c\/li\u003e\n\u003cli\u003eFunction: Supply-air overheat protection\u003c\/li\u003e\n\u003cli\u003eOEM Part Number: 20162906\u003c\/li\u003e\n\u003cli\u003eFits: Goodman \u0026amp; Amana AMS951155DXAB and compatible 95% furnaces\u003c\/li\u003e\n\u003cli\u003eApplication: Gas furnace heat-exchanger limit control\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eOEM vs. Generic\u003c\/h3\u003e\u003cp\u003ePrimary limits are matched to a specific trip temperature and mounting footprint. The \u003cstrong\u003egenuine 20162906\u003c\/strong\u003e guarantees the correct M4 set point and bracket fit; a generic limit with the wrong threshold can cause nuisance lockouts or leave the heat exchanger unprotected. Always replace with OEM.\u003c\/p\u003e\u003ch3\u003eInstallation Difficulty\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eEasy (2\/5)\u003c\/strong\u003e — Two screws and two spade terminals on the burner\/heat-exchanger panel. De-energize the furnace first. If the old limit was tripping, verify filter, blower speed, and duct airflow before returning to service.\u003c\/p\u003e","brand":"Goodman","offers":[{"title":"Default Title","offer_id":63057765204339,"sku":"GOODMAN-7408","price":9.95,"currency_code":"USD","in_stock":true}],"url":"https:\/\/nationalhvacparts.com\/products\/oem-goodman-m4-primary-limit-switch-for-ams951155dxab-20162906","provider":"National HVAC Parts","version":"1.0","type":"link"}