{"product_id":"oem-goodman-m4-primary-limit-switch-for-gch90905dxab-20162906","title":"OEM Goodman M4 Primary Limit Switch for GCH90905DXAB — 20162906","description":"\u003cp\u003eThe Goodman \u003cstrong\u003e20162906 M4 Primary Limit Switch\u003c\/strong\u003e is a genuine OEM high-limit safety control for the Goodman \u003cstrong\u003eGCH90905DXAB\u003c\/strong\u003e gas furnace. Mounted on the heat exchanger, this thermal switch opens the circuit and shuts down the burners if the plenum temperature exceeds its rated set point — protecting the furnace and home from overheating.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003ePart Number: 20162906\u003c\/li\u003e\n\u003cli\u003eType: M4 primary high-limit switch\u003c\/li\u003e\n\u003cli\u003eFunction: Automatic-reset overheat safety shutoff\u003c\/li\u003e\n\u003cli\u003eFits: Goodman GCH90905DXAB high-efficiency furnaces\u003c\/li\u003e\n\u003cli\u003eMount: Heat exchanger \/ vestibule panel\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eOEM vs. Generic\u003c\/h3\u003e\u003cp\u003eOEM Goodman limit switches are calibrated to the exact trip temperature specified for this heat exchanger, ensuring proper safety response. Generic switches may carry different set points or reset behavior, risking short-cycling or, worse, failure to trip. As a primary safety device, OEM replacement is the recommended choice.\u003c\/p\u003e\u003ch3\u003eInstallation Difficulty\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eEasy (2\/5).\u003c\/strong\u003e Two mounting screws and quick-connect terminals — usually a 15-minute repair. Cut power at the disconnect before servicing and match the switch orientation to the original.\u003c\/p\u003e","brand":"Goodman","offers":[{"title":"Default Title","offer_id":63058055135603,"sku":"GOODMAN-9757","price":24.95,"currency_code":"USD","in_stock":true}],"url":"https:\/\/nationalhvacparts.com\/products\/oem-goodman-m4-primary-limit-switch-for-gch90905dxab-20162906","provider":"National HVAC Parts","version":"1.0","type":"link"}