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The Goodman B1370820 is a factory-OEM blower-door safety switch pre-wired with lead harness, designed as a direct replacement for the GMT115-5B gas furnace. This interlock switch cuts power to the blower and burner circuits whenever the access panel is removed, preventing the furnace from operating with the door off. A failing or stuck door switch is a common cause of a furnace that won't start, cycles unexpectedly, or shows a blower-off condition.
Our genuine Goodman OEM switch guarantees exact contact ratings, plunger travel, and connector fit — no splicing or crimping guesswork. Universal generic switches often require rewiring and may not seat flush against the panel, risking nuisance trips. For a safety-critical interlock, OEM is the reliable choice.
Easy (1/5). Disconnect power, unplug the old switch, mount the new one, and reconnect the leads. Typically a 10-minute repair with basic hand tools. Always confirm 24V/line power is off before servicing.