Error Code	Symptom	Fault Type	Guide
C	Humidifier shows 'C' or 'CLEAN' and may beep periodically	Cleaning Reminder / Maintenance Indicator	View Details
DEF	Dehumidifier shows 'DEF' and compressor cycles off frequently	Automatic Defrost Mode	View Details
E1	Humidifier will not run and displays E1 on the control panel	Room Temperature Sensor Fault	View Details
E2	Humidifier shows E2 and stops producing mist	Humidity Sensor / Hygrostat Fault	View Details
E3	Dehumidifier displays E3 and stops dehumidifying	Room Temperature Out of Range / Defrost Sensor Error	View Details
E4	Dehumidifier shows E4 and will not run the compressor	Refrigerant System / High or Low Pressure Protection	View Details
E5	Dehumidifier displays E5 and stops operation	Humidity Sensor Failure (Dehumidifier)	View Details
E6	Dehumidifier shows E6 and will not start	Internal Communication Error / Control Board Fault	View Details
F	Humidifier display shows letter 'F' and unit stops or will not start	Water Level / Float Switch Fault	View Details
FILL	Display shows 'FILL' or water droplet icon flashes and unit stops producing mist	Empty Tank / Low Water Condition	View Details
FILTER	Dehumidifier displays 'FILTER' or filter icon and may beep	Air Filter Maintenance Reminder	View Details
–	Dehumidifier bucket fills too quickly or overflows	Excessive Condensate / Drainage Fault	View Details
–	Dehumidifier does not start and bucket full light stays on even when bucket is empty and correctly inserted	Bucket Full Switch Stuck or Failed	View Details
–	Dehumidifier fan does not run but compressor is trying to start	Fan Motor Failure (Dehumidifier)	View Details
–	Dehumidifier frost buildup on evaporator coil and poor water removal	Coil Icing / Defrost System Problem	View Details
–	Dehumidifier runs but does not collect water in the bucket	No Dehumidification / Refrigeration System Issue	View Details
–	Dehumidifier runs but room humidity does not decrease	Ineffective Dehumidification / Airflow or Sizing Issue	View Details
–	Humidifier base shows corrosion or rust around electrical contacts	Water Ingress / Corrosion Damage	View Details
–	Humidifier display and buttons are unresponsive or behave erratically	Control Panel / Keypad Failure	View Details
–	Humidifier does not power on at all (no lights, no display)	No Power / Power Supply Failure	View Details
–	Humidifier emits a strong white dust on nearby surfaces	Mineral Dust Emission from Ultrasonic Operation	View Details
–	Humidifier fan runs but no air seems to come out	Blocked Air Outlet / Fan Housing Obstruction	View Details
–	Humidifier leaks water onto the table or floor	Water Tank or Base Leakage	View Details
–	Humidifier mist is cold when warm mist is expected (on models with preheating)	Preheater / Heating Element Failure	View Details
–	Humidifier or dehumidifier emits unpleasant musty or moldy odor	Microbial Growth in Water Path or Air Ducts	View Details
–	Humidifier or dehumidifier makes loud rattling or grinding noises	Fan Motor or Blower Imbalance	View Details
–	Humidifier or dehumidifier vibrates excessively and moves on the surface	Mechanical Imbalance / Mounting Issue	View Details
–	Humidifier powers on but produces no mist	Ultrasonic Transducer / Nebulizer Failure	View Details
–	Humidifier produces very weak mist output even at maximum setting	Restricted Mist Path / Partial Transducer Scaling	View Details
–	Humidifier shuts off unexpectedly even though the tank is full	False Low-Water Detection	View Details
–	Humidifier turns on and off rapidly or cycles every few seconds	Control Logic Instability / Sensor Feedback Issue	View Details
–	Humidifier water consumption is much higher than expected	Over-Humidification / Control Calibration Issue	View Details
–	Humidifier water level in base does not drop even though mist is produced	Tank Not Refilling Base Properly	View Details
–	Humidifier water tank is difficult to remove or install, and unit may not run	Tank Alignment / Latching Problem	View Details

Boneco Humidifiers & Dehumidifiers Error Codes

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