{"product_id":"oem-goodman-m4-primary-limit-switch-for-amh80603axaa-20162906","title":"OEM Goodman M4 Primary Limit Switch for AMH80603AXAA — 20162906","description":"\u003cp\u003eThe \u003cstrong\u003eGoodman 20162906 M4 primary limit switch\u003c\/strong\u003e is a genuine OEM auto-reset high-limit control for \u003cstrong\u003eAMH80603AXAA\u003c\/strong\u003e gas furnaces and compatible Goodman\/Amana models. Mounted on the heat exchanger bulkhead, the primary limit monitors supply-air temperature and cuts the gas valve if the furnace overheats — typically from restricted airflow such as a dirty filter or failed blower. Once the temperature drops, this M4-style switch resets automatically, making it the furnace's front-line thermal protection.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eType: Primary high-limit switch (M4 series)\u003c\/li\u003e\n\u003cli\u003eAction: Normally closed, auto-reset on cool-down\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: AMH80603AXAA and compatible Goodman\/Amana furnaces\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eOEM vs. Generic\u003c\/h3\u003e\u003cp\u003eOEM 20162906 is set to your furnace's exact cut-out temperature and mounting-bracket profile, ensuring correct protection and a clean fit. Generic limits with different trip points or bracket shapes can short-cycle the furnace or fail to seat properly. Match the OEM set point exactly on any primary limit.\u003c\/p\u003e\u003ch3\u003eInstallation Difficulty\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eEasy\u003c\/strong\u003e — two mounting screws and two spade terminals. Shut off power first. Plan 10–15 minutes. If the furnace keeps short-cycling on limit afterward, check the filter, blower, and ductwork for airflow restriction.\u003c\/p\u003e","brand":"Goodman","offers":[{"title":"Default Title","offer_id":63057605329267,"sku":"GOODMAN-5123","price":9.95,"currency_code":"USD","in_stock":true}],"url":"https:\/\/nationalhvacparts.com\/products\/oem-goodman-m4-primary-limit-switch-for-amh80603axaa-20162906","provider":"National HVAC Parts","version":"1.0","type":"link"}