E20 error and unit indicates communication failure with remote display or wireless module (if equipped)

Safety first: Unplug the unit before connecting or disconnecting any communication cables.

• Check cabling: Inspect the cable between the Watersoft main control and any remote display or external module. Ensure both ends are fully seated and the cable is not damaged.
• Power cycle modules: Disconnect power to both the softener and remote module for 5 minutes, then restore power and allow them to re-establish communication.
• Verify wireless pairing: For wireless modules, follow the Watersoft pairing procedure to re-link the devices. Ensure they are within the specified range and not blocked by heavy walls or metal.
• Module substitution: If possible, test with a known-good remote module. Replace the faulty module if E20 clears with the substitute.

If communication errors persist with known-good modules and cables, the main control board’s communication port may be defective.