E3 code moisture

Capacitor
If your dehumidifier is no longer pulling water from the air and you have verified that the ambient room temperature is above 65 degrees Fahrenheit, then the unit's compressor may not be running. The compressor is the pump that circulates the refrigerant through the evaporator to extract moisture from the air. There is a capacitor in the compressor circuit to help the compressor motor to start and if the capacitor has failed then the compressor won't run. If the compressor doesn't run or if the overload device continues to trip, then you may have a defective capacitor. An accurate diagnosis can be determined by a qualified person using special test equipment.
Overload
If your dehumidifier is no longer pulling water from the air and you have verified that the ambient room temperature is above 65 degrees Fahrenheit, then the unit's compressor may not be running. The compressor is the pump that circulates the refrigerant through the evaporator to extract moisture from the air. There is a device in the compressor circuit called an overload and it is used to protect the compressor motor from damage. If the overload has failed then the compressor won't start. If you have verified that the compressor doesn't run, then you can test the overload for continuity with a multi-meter. A common cause for the overload to fail is from operating the dehumidifier on long or undersized extension cords.
Fan Motor

If your dehumidifier is not making water and you have verified that the ambient temperature is above 65 degrees Fahrenheit, then you may have a faulty fan motor. For proper operation, a dehumidifier needs to have an adequate amount of air blowing across the evaporator coils to prevent frost or ice buildup. If you feel little or no air coming through the grille area and the filter is clean, then remove the cover and check the fan area. Inspect the coils to make sure that they are not restricted with lint or dirt and clean them if necessary. Make sure that the fan motor rotates freely and that the fan blade or blower wheel is firmly attached to the motor shaft. Using caution, operate the unit in a fan only mode and observe the fan motor. If it hums but does not rotate or only rotates slowly then it is defective and will need to be replaced. If the motor does not rotate and does not appear to make any sound, it may still be defective, but will require further testing by someone who is comfortable with using a multi-meter and working with live electrical circuits.
Electronic Control Board or PCB Assembly

If your dehumidifier is no longer pulling water from the air and you have verified that the ambient room temperature is above 65 degrees Fahrenheit, then the unit's compressor or fan motor may not be operating. The compressor is the pump that circulates the refrigerant through the evaporator, and the fan motor blows air across the evaporator coils to extract the moisture. On some modern dehumidifiers an electronic control board, often called the PCB, is used to control the compressor and fan motor. The control board has sensors connected to it that monitor the relative humidity and when the level is higher than the control setting, the control board will activate relays to turn on the compressor and fan motor. If you have an electronic control model and the compressor or the fan is not operating, then the electronic control may be at fault. A voltage test, using a multi-meter at the output relays, would be required to help in the diagnosis as well as confirmation that the sensors are operating normally.

It sounds like what you hear working is the fan. The unit also has a compressor; if the compressor is bad or the freon is gone, the fan will run but the coils wont cool to remove moisture from the air.

is compressor running fan maybe compressor must be running for dehum to take the compressor has a distint sound should be easy to tell by sound

Short on refrigerant... or a failed compressor. are most likely or a system problem, causing it to trip off.

There may also be a failed electrical component, you need to check for voltage at the compressor.

cheers

Assuming there is moisture in the air, it could be several things. Be sure the unit is clean and the compressor and fan are running. If not it probably is the humidstat. The outlet line from the compressor should be warm and the return cold. If they are not and the compressor is operating you either have lost refrigerant or the compressor has failed.
Good Luck,
Gilsh

could have overheated the compressor if the filter was really dirty and blown it

What do you have the humidity level set at on your dehumidifier? The average is 65%. Make sure you do not have it set at 75% because if you do this could be causing it to keep the humidity so high.

By condenser I assume you mean the compressor is running. Is there ice forming on the front coil?

Calling two service centers, they both indicated that the main circuit board needed replacing. This would need shipping the unit!!, part and then labor. I figured over $120 - not reasonable. I then took the unit apart and followed the wires from the compressor to the back of the unit. This is where the moisture sensor was located - upper left. You'll see this when you take the filter off. Anyway, I cleaned the face of this part with a old toothbrush, used some compressed air to remove any dust. I then followed the wires with the black sleeve that went to what I think is a temperature sensor - also on the left. The wires go to a sensor that is pushed into a copper tube that is part of the cooling tubing. Gently pull this out, wipe it down and re-install. I then plugged the unit in, set the humidity level and it now works. I just put the unit back together and the compressor is turning on and collecting moisture! I will run it a few days and keep checking on it to make sure it doesn't go into the 'E3' Mode. By the way, the repair shops I called really didn't have a clue what the E3 code was. Dennis