Display shows SPAO; the heater does not respond to thermostat changes.

Overview: The ambient sensor helps the SmartPool heater manage ignition and freeze protection.

• Locate sensor: Find the small probe or thermistor labeled as ambient or air sensor on the heater cabinet or control area.
• Inspect placement: Ensure it is not touching hot metal, exhaust, or in direct sunlight, which can cause false readings.
• Check wiring: With power off, verify the sensor leads are intact and firmly plugged into the control board.
• Reset: Restore power and see if SPAO clears. If not, the ambient sensor is likely defective and should be replaced with a SmartPool-approved part.