Furnaces

Furnace work is sail switches, limit switches, igniters and boards — small parts with a lot of part numbers between them. The diagrams show how the blower housing, burner and gas valve sit together so you can order the right revision.

Two switches that look the same

Sail and limit switches are easy to confuse in the housing and are not interchangeable. The callout numbers keep them apart.

Match the gas valve to the board

Valve and control board are a matched pair on several models. Identify both together rather than replacing one and hoping.