Levoit humidifier displays E1 and will not run or shuts off immediately after power-on.

Safety first: Unplug the humidifier before opening any covers. Never work on the unit while it is connected to power or filled with water.

Steps to check and correct:

• Power reset: Unplug the unit for 5–10 minutes, then plug back in and try again. Sometimes E1 is a temporary logic error.
• Inspect sensor cable: On most Levoit console humidifiers, the room temperature sensor is a small NTC probe wired to the main PCB. Remove the water tank, then the base cover (usually Phillips screws). Locate the thin two‑wire harness going to a small probe near the air outlet or intake.
• Check connections: Ensure the sensor plug is fully seated on the main board. Gently unplug and re‑plug the connector several times to clear oxidation.
• Visual inspection: Look for broken, pinched, or corroded wires. If the insulation is cut or the wires are broken, the sensor assembly must be replaced.
• Replace sensor if needed: If E1 persists, replace the NTC temperature sensor assembly with a compatible Levoit sensor (match connector style and resistance rating). Route the new sensor wiring exactly as the original to avoid fan contact.
• Control board check: If a known‑good sensor still gives E1, the temperature input circuit on the main PCB is likely damaged. In that case, replace the main control board or contact a qualified technician.