E20 displayed and unit reports communication error between display and main control
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Unplug the softener before opening the control housing. Avoid static discharge by touching a grounded metal object before handling boards.
Step-by-step:
- Reseat ribbon cable: Remove the AquaUnique control cover and locate the communication ribbon between the display and main board. Carefully unplug and replug both ends.
- Inspect connectors: Check for bent pins, corrosion, or moisture. Clean lightly with electronics cleaner if needed.
- Check mounting: Ensure both boards are securely mounted and not flexing or moving when buttons are pressed.
- Power test: Restore power and see if E20 clears. Gently tap the housing to ensure the error does not recur with vibration.
When to call a technician: Persistent E20 usually indicates a failing display or main board that should be replaced as a matched set.
Repair Difficulty
Required Part
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