Tune-Up Kit comes in two variations. Kit #1 is a single sense electrode (1 wire that goes to the electrode, applicable to S/N above 920500001), Kit #2 is a dual sense electrode (2 wires that go to the electrode, applicable to S/N below 920500001). Please verify which kit is applicable to your furnace prior to ordering.
Tune-Up Kit #1 Contents (Links):
Tune-Up Kit #2 Contents (Links):
SUBURBAN FURNACE NT-30SP EXPLODED PARTS VIEW LINKS