Code 42 — Furnace Inducer Fault

What does 42 mean?

This fault indicates a problem with the inducer motor in the furnace. The inducer motor draws combustion byproducts out of the furnace and ensures safe operation.

• Inducer motor failure
• Blocked exhaust vent or flue pipe
• Pressure switch malfunction
• Wiring issue to the inducer motor

Click steps to track your progress.

1. 1

   Turn off power to the furnace at the circuit breaker for 30 seconds to attempt a reset.

2. 2

   Ensure the furnace exhaust and intake vents (if applicable) are clear of obstructions.

3. 3

   Listen for the inducer motor to hum or spin when the furnace attempts to start.

4. 4

   If the inducer motor does not operate, contact a qualified HVAC technician for inspection.