Draft Inducer Motor Replacement: A Homeowner's Guide

The draft inducer motor (also called the induced draft blower or venter motor) is a small fan that draws combustion gases through the heat exchanger and out the flue before ignition begins. In modern induced-draft and condensing furnaces, it's the first component to run when a heat call comes in. If it fails, the furnace will never get past the first step of its startup sequence.

Symptoms of a Failed Draft Inducer

  • Furnace shows a "pressure switch" fault code but the pressure switch itself tests good
  • You can hear the furnace trying to start but nothing spins up in the first few seconds
  • Inducer runs but makes loud grinding, squealing, or rattling noise
  • Inducer runs intermittently — sometimes it starts, sometimes it doesn't
  • Inducer runs but pressure switch still shows open (inducer not creating enough draft)

Diagnosing the Inducer vs. the Pressure Switch

A pressure switch fault can come from the inducer OR the pressure switch itself. Before replacing the inducer, test the pressure switch:

  1. Locate the rubber tubing connecting the pressure switch to the inducer housing
  2. Disconnect the tube at the pressure switch end
  3. Gently blow into the tube while the furnace is calling for heat — if the furnace continues past the pressure switch check, the switch is fine and the inducer is failing to create adequate draft

Also listen carefully. A worn inducer bearing typically makes noise — squealing, grinding, or a rhythmic wobble. If it's spinning quietly but not creating draft, check the wheel for debris or confirm the wheel isn't slipping on the shaft.

Finding the Right Replacement

Draft inducer motors are not universal. The correct replacement depends on your furnace model. You need either:

  • The furnace model number (on a label inside the front panel) — cross-reference to the inducer part number
  • The part number on the existing motor (printed on the motor label)

Key specs to match: voltage (typically 115V or 120V), RPM, rotation direction (viewed from the shaft end), mounting configuration, and flange size. Fasco is the dominant OEM inducer manufacturer — their part numbers (e.g., A161, A065, A115, A200 series) are widely cross-referenced. Many OEM inducers are Fasco units with a furnace brand label on them.

Replacing the Inducer Motor

  1. Shut off power and gas to the furnace
  2. Photograph the existing inducer, noting orientation, wire routing, and flue connection
  3. Disconnect the electrical connector and the flue pipe from the inducer outlet
  4. Disconnect the pressure switch tubing
  5. Remove the mounting screws (usually 3–4 screws securing the inducer housing to the collector box)
  6. The entire inducer assembly — housing and motor — lifts away
  7. If replacing just the motor (not the housing), transfer the wheel from the old motor to the new one — it's typically press-fit onto the shaft
  8. Mount the new inducer, reconnect all connections, and restore power and gas

After Installation

Restore power and initiate a heat call. Watch the inducer spin up — it should run for 20–30 seconds before the igniter activates. Confirm the pressure switch closes (furnace proceeds to ignition). Listen for any unusual noise from the new inducer for the first few cycles.

New England Supply House stocks Fasco draft inducers and OEM inducer assemblies for major furnace brands. Use our cross-reference guide or call 774-701-6374 with your furnace model number.

Browse Fasco draft inducer motors →

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