How to Replace a Furnace Sequencer

An electric furnace sequencer is a switching component that activates different heating elements in the furnace as needed. The component manages the power surge when an element switches on. Due to the high amperage draw of the heating elements, switching on all elements at once would likely blow a fuse or trigger the circuit breaker. Replacing a sequencer takes less than an hour.

Screwdriver set
Wire strippers

Instructions

- 1
  Flip off the circuit breaker controlling the electric furnace at the breaker box. Wait for the unit to reach room temperature.
- 2
  Take off the furnace access cover using a screwdriver to remove the slotted bolts. The sequencer is a rectangular part mounted near the top with multiple wire pairs connected to the side or bottom. The number of wires depends on the number of heating elements in your particular model.
- 3
  Write a reference note on a piece of masking tape and attach to each wire to indicate where it connects on the sequencer.
- 4
  Loosen the screw holding each wire to the sequencer to pull off the wire.
- 5
  Remove the mounting screws holding the sequencer inside the furnace. Remove the old part.
- 6
  Attach the new sequencer to the furnace mount and secure with the screws.
- 7
  Fasten each wire to a screw terminal on the sequencer using the notes on masking tape labels to guide your connections. Tighten all screws.
- 8
  Remove the masking tape labels and replace the cover panel on the furnace. Flip on the circuit breaker controlling the electricity.
- 9
  Switch on the electricity at the fuse box or breaker.

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