Dehumidifier frequently freezes up; evaporator coil covered in ice

Safety: Unplug the unit before defrosting. Do not chip ice with sharp tools; you can damage the coil.

Steps:

• Defrost completely: Turn the unit off and let it sit unplugged until all ice melts. Place towels under the unit to catch water.
• Clean filter and coils: Wash the air filter and clean dust from both coils to restore airflow.
• Check room temperature: Use a thermometer to ensure the room is within the recommended range. Move the unit to a warmer area if needed.
• Sensor check: Inspect the evaporator thermistor to ensure it is firmly attached to the coil and wiring is intact. Replace if damaged.
• Monitor operation: After cleaning and relocating, run the unit and periodically check the coil. Light, even frost that cycles off is normal; heavy ice buildup is not.

When to call a technician: Persistent icing with good airflow and correct room temperature may indicate low refrigerant or a defrost control issue requiring professional service.