IMAGE COMING SOON
OEM Guaranteed
Same-Day Ship
30-Day Returns
Secure Checkout
Protect your furnace with the genuine OEM Goodman B1370155 Auxiliary Limit Switch, a direct-fit safety control for GMNT045-3B and compatible Goodman and Amana gas furnaces. This auxiliary limit typically mounts on the blower housing to guard against overheating in the blower compartment — a common secondary protection point that supplements the primary limit on the heat exchanger.
OEM B1370155 arrives pre-calibrated to the 120°F auto-reset spec Goodman engineered for this furnace platform. Universal aftermarket limits frequently require you to match trip temperature by hand and may not seat flush in the factory bracket. Choosing OEM removes the guesswork and keeps the manufacturer's safety margins intact.
Difficulty: Easy (1/5). Plan on 10–15 minutes. De-energize the furnace at the disconnect, unplug the two spade terminals, remove the mounting screws, swap in the new switch, and reconnect. Confirm the blower cycles normally on a test run. Repeated auxiliary-limit trips usually point to restricted airflow — check the filter, ductwork, and blower speed before assuming the switch has failed.