Status LED flashes five times, furnace will not start heating cycle, inducer may not run.

Safety First: Turn off power and gas before inspecting wiring or flame sensor. Do not bypass safety circuits.

This code indicates the control board is detecting flame when there should be none.

• Inspect flame sensor and wiring: Remove the burner access panel. Check the flame sensor rod for damage or contact with metal surfaces other than its mounting bracket. Ensure the sensor wire is not pinched or touching the burner or cabinet.
• Clean flame sensor: Remove and gently clean the sensor rod with fine steel wool. Reinstall and ensure proper clearance from the burner flame path.
• Check for cross-lighting from other appliances: In shared vent systems, ensure no other appliance is backdrafting flame or hot gases into the Thermo Pride furnace.
• Inspect control board: Look for signs of moisture, corrosion, or burnt components on the integrated furnace control. Ensure all ground connections are tight.
• Reset power: Restore power and call for heat. If the code returns immediately before any ignition attempt, the control board may be defective.

When to call a professional: If wiring and sensor are intact and the false flame code persists, have a technician test and possibly replace the control board.