E10 error and water remains hard even after recent regeneration

Safety first: Use caution when working around the brine tank; salt can be heavy and dusty. Wear gloves and eye protection.

• Check bypass position: Ensure the Watersoft bypass valve is fully in the service position and not partially bypassing hard water.
• Verify salt level and condition: Open the brine tank and confirm there is adequate salt. Break up any solid crust (salt bridge) by gently pushing a broom handle down through the salt until you reach water. Remove mushy salt if necessary.
• Reprogram settings: Confirm hardness, capacity, and salt dose are set per your water test and Watersoft manual. Increase salt dose slightly if hardness is high.
• Manual regeneration: Initiate a manual regeneration and test water hardness 24 hours later. If water is still hard, the resin may be exhausted or iron-fouled.
• Resin inspection: If possible, remove a small sample of resin from the tank. If beads are broken, mushy, or heavily discolored, plan to replace the Watersoft cation resin.

Persistent E10 after correcting settings and salt issues usually indicates the need for a full resin replacement.