E20 error and unit indicates excessive regeneration frequency

Safety first: No special electrical or plumbing hazards for this check, but use caution when adjusting programming.

• Check for leaks: Inspect toilets, humidifiers, and RO systems for continuous running that could cause high water usage.
• Verify hardness: Test raw water hardness with a test kit and adjust the Waterguy hardness setting to match actual conditions.
• Review capacity settings: Ensure the grain capacity and reserve are set per the resin tank size and household usage.
• Flow meter check: As with E05, clean and verify the flow meter is not stuck or miscounting.

After correcting leaks and settings, clear E20. If regenerations remain abnormally frequent, consult a technician to verify sizing and meter operation.