Zodiac pool heater shows E06; heater does not respond properly to temperature settings.

Safety: Turn off power before accessing the control compartment or water manifold.

• Locate the thermistor: The water temperature sensor is typically threaded into the header/manifold or installed in a sensor well. Follow the sensor cable back to the control board.
• Inspect connections: Check for corrosion, moisture, or loose pins at the sensor plug and control board connector. Clean and dry as needed.
• Test sensor resistance: With power off and sensor disconnected, measure resistance with a multimeter and compare to Zodiac's temperature/resistance chart. A shorted or open sensor must be replaced.
• Replace sensor: If readings are out of spec, remove the old thermistor (be prepared for some water leakage) and install a new Zodiac-compatible water temperature sensor using thread sealant approved for potable water.
• Re-test operation: Restore power and verify that the displayed water temperature is reasonable and that E06 is cleared.