Dehumidifier: Why won't my dehumidifier turn on?

The electronic control board regulates the dehumidifier's compressor and fan motor. If the electronic control board doesn't activate the compressor and fan properly, replace the electronic control board.

The user interface control board in the control panel houses the selection buttons you push. A wire harness connects the user interface control board to the control board. If the selection buttons don't respond when you push them, replace the user interface control board.

The evaporator thermistor is a temperature sensor on the evaporator coils. It communicates the temperature of the evaporator coil to the electronic control board; if the temperature is too low, the electronic control board detects excessive frost and begins the defrost cycle. If the thermistor isn't working properly, the electronic control won't defrost the coils. Replace the evaporator thermistor if it doesn't detect the evaporator temperature.

The humidistat is a sensor on the front of the evaporator coil that monitors the humidity of the room air being pulled in through the evaporator. The humidistat communicates the humidity to the electronic control board through a wire harness connection. If the thermistor is defective, the electronic control won't properly detect humidity and dehumidify the room. Replace the humidistat if it doesn't sense the humidity.

The compressor is a pump that compresses the refrigerant that runs through the sealed system in the dehumidifier. If the compressor doesn't run when activated, have a refrigerator service technician replace it; by law, an EPA-licensed technician must complete this repair because it involves refrigerant.