How to Change a Rollout Limit on a White Rodgers Furnace

Shut off the electricity to the furnace while replacing the rollout limit switch. Check for a dedicated "On/Off" switch on or near the furnace. Open your electrical service panel and flip the corresponding circuit breaker switch to the "Off" position if your model doesn't have an "On/Off" switch.

Remove the front service-access panel; the panel may be secured with screws or retaining clips, depending on your furnace model. Take out the screws or slide the panel straight up to disengage the retaining clips. Remove only the burner access panel if your furnace has two front service panels; this is the lower panel on downflow furnaces and the upper panel on upflow models.

Find the rollout limit switch near the gas furnace burners. Look for a small, rounded component with two wires attached to it. Pull the wire connectors off of the rollout limit switch terminals using a pair of needle-nose pliers. Remove the screws securing the old rollout limit switch; the type and number of screws varies by model. Discard the removed switch, but reserve the mounting screws.

Align the screw holes on the burner compartment with the screw holes on the replacement rollout limit switch. Reinsert the mounting screws and tighten them to secure the new component. Clip the removed wires to the rollout limit switch terminals.

Replace the removed service-access panel. Restore the electrical supply to the furnace.