Furnace displays E17; unit may not start or may shut down unexpectedly.

Safety: Turn off power and gas before working near burners.

• Inspect wiring: Trace the flame sensor wire from the sensor to the control board. Look for cuts, melted insulation, or points where the conductor may touch the furnace chassis. Repair or replace the wire as needed.
• Sensor terminal: Ensure the flame sensor terminal is clean and dry. Wipe away any moisture or corrosion.
• Routing: Reroute the wire away from sharp edges and hot surfaces, securing it with high-temperature-rated clips or ties.
• Control board: If wiring and sensor are good but E17 persists, the flame sense circuit on the Wolf control board may be damaged and require replacement.