Display shows E5 and the unit shuts off or refuses to start; sometimes accompanied by a burning smell previously.

Safety first: Unplug immediately. Do not attempt to restart until the fault is identified. Risk of electric shock and fire.

• External check: Inspect the power cord and plug for cuts, burns, or deformation. Replace the power cord set if damaged.
• Internal fuse: Remove the housing and locate the internal glass or ceramic fuse on the main control board. Test with a multimeter; replace only with the same rating if blown, and investigate the cause of failure.
• Check for shorts: Visually inspect the heater, fan motor, and wiring for melted insulation or contact with metal chassis. Use a multimeter to check for continuity between live conductors and ground/chassis—there should be none.
• Component isolation: Disconnect the heater and fan motor one at a time and test resistance. A very low resistance (near 0 Ω) or continuity to chassis indicates a shorted component that must be replaced.
• Board inspection: Examine the main PCB for burnt tracks, bulging capacitors, or cracked components. Replace the main control board if any damage is found or if the fuse repeatedly blows.