{"product_id":"oem-goodman-m4-primary-limit-switch-amvm970803bnba-20162906","title":"OEM Goodman M4 Primary Limit Switch AMVM970803BNBA — 20162906","description":"\u003cp\u003eThe \u003cstrong\u003eGoodman 20162906 M4 Primary Limit Switch\u003c\/strong\u003e is a genuine OEM high-limit safety control for the \u003cstrong\u003eAmana\/Goodman AMVM970803BNBA\u003c\/strong\u003e modulating variable-speed gas furnace. Mounted on the heat exchanger\/plenum, this primary limit monitors supply-air temperature and opens the control circuit if the furnace overheats — typically from restricted airflow such as a clogged filter, closed vents, or a failing blower. It is the furnace's main over-temperature protection during normal heating cycles.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Part #:\u003c\/strong\u003e 20162906\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFits Model:\u003c\/strong\u003e AMVM970803BNBA (AMVM97 modulating series)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eType:\u003c\/strong\u003e M4 primary high-limit switch (auto-reset)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFunction:\u003c\/strong\u003e Opens circuit on plenum over-temperature\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Goodman \/ Amana OEM\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eOEM vs. Generic:\u003c\/strong\u003e The primary limit is calibrated to a specific trip and reset temperature matched to this furnace's heat exchanger and airflow design. The genuine 20162906 uses Goodman's engineered M4 set point; a mismatched generic switch causes nuisance short-cycling or fails to protect the heat exchanger. As a safety control, it should always be replaced with the exact OEM part.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eInstall Difficulty: Moderate (2\/5).\u003c\/strong\u003e Turn off gas and power at the disconnect. Photograph and disconnect the wiring, remove the mounting screws, and install the new limit on the same bracket location so its sensing element sits correctly in the airstream. Reconnect, restore power, and run a full heat cycle to confirm normal shutdown at end of call. Address any underlying airflow restriction before returning the furnace to service.\u003c\/p\u003e","brand":"Goodman","offers":[{"title":"Default Title","offer_id":63058005098867,"sku":"GOODMAN-9274","price":27.95,"currency_code":"USD","in_stock":true}],"url":"https:\/\/nationalhvacparts.com\/products\/oem-goodman-m4-primary-limit-switch-amvm970803bnba-20162906","provider":"National HVAC Parts","version":"1.0","type":"link"}