Dehumidifier shows H24 and stops; may occur during defrost or in cold rooms.

Safety first: Disconnect power.

• Identify defrost sensor: Often the same or an additional thermistor on the evaporator coil used for defrost control.
• Check mounting: Confirm the sensor is in good thermal contact with the coil (clipped or strapped). Reattach securely if loose.
• Inspect for ice buildup: Excessive ice can stress the sensor. Defrost the unit by leaving it unplugged with panels removed until all ice melts, then dry thoroughly.
• Test sensor: Measure resistance at known temperatures (e.g., room temperature and after cooling the sensor in ice water) and compare to spec. Replace if readings are abnormal.
• Replace PCB if needed: If sensor and wiring are good, the defrost control on the main PCB may be faulty and require replacement.