Venta digital humidifier will not start and displays E1 on the control panel

Safety first: Unplug the humidifier from the mains before opening any covers. Never work on the unit while it is connected to power.

• Power reset: Unplug the unit for 5–10 minutes, then plug it back in and try to start it. Sometimes E1 is a temporary sensor read error.
• Check sensor location: Ensure the unit is not placed directly in front of a heater, in direct sunlight, or in a cold draft. Extreme localized temperatures can trigger sensor errors.
• Inspect the temperature sensor: Remove the top housing according to the user manual. Locate the small NTC sensor (usually a small bead or capsule on two thin wires near the air intake). Check that it is firmly plugged into the main control PCB and that the wires are not pinched or broken.
• Clean dust and corrosion: If the sensor connector or PCB pins show oxidation, gently clean with a dry, soft brush or electronics contact cleaner (with the unit unplugged). Allow to dry completely before reassembly.
• Test or replace sensor: If you have a multimeter, measure the resistance of the NTC sensor and compare with the service chart for your Venta model (resistance should change smoothly with temperature). If it is open, shorted, or far out of range, replace the NTC room temperature sensor.
• Control board check: If a known-good sensor still gives E1, the main control PCB sensor input may be defective. At this point, replacement of the main control PCB is recommended and is best done by a qualified technician.