E17 error, and the unit reports brine tank temperature out of range.

Safety first: Unplug the unit before handling any sensors or wiring. Avoid working in standing water around the softener.

Step-by-step:

• Check environment: Ensure that the softener is installed in a location within the recommended temperature range (typically 2–40°C). Protect it from freezing.
• Inspect sensor: Locate the AquaUnique brine tank temperature sensor (if equipped) and verify that it is securely mounted and not physically damaged.
• Check wiring: Follow the sensor cable to the control head and ensure that connectors are tight and free of corrosion.
• Power cycle: Restore power and see if E17 clears after the unit stabilizes at room temperature.

When to call a technician: Persistent E17 with normal ambient temperature indicates a failed sensor or control board that should be replaced.