{"product_id":"oem-goodman-m4-primary-limit-switch-for-gch90905dxaa-20162906","title":"OEM Goodman M4 Primary Limit Switch for GCH90905DXAA — 20162906","description":"\u003ch2\u003eGoodman 20162906 M4 Primary Limit Switch\u003c\/h2\u003e\u003cp\u003eThe \u003cstrong\u003e20162906\u003c\/strong\u003e is a genuine OEM primary high-limit switch engineered for the Goodman \u003cstrong\u003eGCH90905DXAA\u003c\/strong\u003e gas furnace and compatible 90% AFUE models. This normally-closed thermal safety control monitors heat-exchanger and plenum temperature, opening the gas-valve circuit to shut the burner down if the furnace overheats — protecting the heat exchanger and your home from a dangerous over-temperature condition. A failed or drifting limit switch is a common cause of short-cycling, no-heat calls, and nuisance lockouts.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003ePart number: 20162906 (M4 primary limit)\u003c\/li\u003e\n\u003cli\u003eType: Manual\/auto-reset thermal high-limit switch\u003c\/li\u003e\n\u003cli\u003eContacts: Normally closed (opens on temperature rise)\u003c\/li\u003e\n\u003cli\u003eFits: Goodman GCH90905DXAA and compatible furnaces\u003c\/li\u003e\n\u003cli\u003eApplication: Gas furnace primary safety limit\u003c\/li\u003e\n\u003cli\u003eBrand: Goodman OEM\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eOEM vs. Generic\u003c\/h3\u003e\u003cp\u003eOur \u003cstrong\u003eOEM Goodman\u003c\/strong\u003e unit is calibrated to the exact factory trip temperature and mounting footprint, ensuring correct safety operation and preserving your equipment warranty. Aftermarket \u003cstrong\u003egeneric\u003c\/strong\u003e limits are lower cost but may trip at slightly different temperatures — acceptable for out-of-warranty budget repairs, but we recommend OEM for a safety-critical control like this.\u003c\/p\u003e\u003ch3\u003eInstall Difficulty\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eEasy (2\/5).\u003c\/strong\u003e Remove power, disconnect two spade terminals, unscrew the mounting bracket, and reverse to install. Typical replacement time is 15–20 minutes for a homeowner comfortable with basic tools. Always disconnect power at the breaker before servicing.\u003c\/p\u003e","brand":"Goodman","offers":[{"title":"Default Title","offer_id":63058054775155,"sku":"GOODMAN-9745","price":19.95,"currency_code":"USD","in_stock":true}],"url":"https:\/\/nationalhvacparts.com\/products\/oem-goodman-m4-primary-limit-switch-for-gch90905dxaa-20162906","provider":"National HVAC Parts","version":"1.0","type":"link"}