My Dehumidifier Has an Error Code

*This article refers to 1st generation WatchDog dehumidifiers

Potential Issue #1- HI Error Code

If the display is showing HI, that means the room temperature is higher than the operating temperature of the dehumidifier (above 105°F).

How to Fix It:

The machine won’t begin running until you either modify the temperature or simply allow the temperature to return to a normal range. Unplug the unit until the temperature has dropped, then plug it back in and resume using.

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Potential Issue #2- LO Error Code

If you see a LO error code on your display screen, then the room temperature is below the operating range of the dehumidifier (below 33°F).

How to Fix It:

Change the conditions so the the temperature is higher than 33°F or wait until the temperature naturally rises. Unplug your dehumidifier until the temperature has risen above 33°F.

*NOTE: If the temperatures are consistently below freezing, your dehumidifier may require some routine maintenance prior to operation. See this post for details—> 5 Ways to Prepare Your Dehumidifier for Summer

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Potential Issue #3- E1 Error Code

If you see an E1 on the display screen, then there is an issue with the humidity sensor.

E1 sensor error code

How to Fix It:

First, check to ensure that the sensor wire is plugged in on both sides (at the sensor and at the control board). If the wire is plugged in properly but you still see an E1 code, you may need to replace the sensor. For help in diagnosing whether you need a replacement sensor, feel free to contact technical support.

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Potential Issue #4- E4 Error Code

An E4 error will display as a warning that your pump is full of water and not working properly. Keep in mind that the WatchDog 900c is the only model with an integrated pump so typically, an E4 error will occur on the 900c. If you have an external pump plugged into your 550 or 900, it is possible to get an E4 code on the gravity drain model.

E4 pump error code

How to Fix It:

To fix an E4 error on your 900c, the first step is to ensure that the pump is properly plugged in at the control board and at the quick connects (for help, setting up your pump, check out this video). If the pump is properly hooked up, next check to see if the pump is is clogged or needs cleaning (for help cleaning the pump, check out this how to page). If the pump is plugged in, clean, and still not working, it’s time to check if the pump is working properly. To check this:

1. Unplug the unit for 2 minutes, then plug it back in. This should reset the error code.

2. Once you plug the unit back in, the pump should initiate to pump out the water that is backed up.

3. At this point, the E4 error code may return as a warning. Simply unplug the unit for 2 minutes, plug it back in, and you should be all set.

If the error code remains, you may have a faulty pump that needs replacing. For help in diagnosing whether you need a replacement pump, feel free to contact technical support. If you have an E4 error occur because of an external pump, refer to the pump’s manual for assistance.