Heater display shows erratic or fluctuating temperature readings.

Safety first: Turn off power before handling sensor wiring.

• Check connections: Inspect the connectors for the Nirvana water temperature sensor(s) at the control board. Reseat and secure them.
• Inspect cable routing: Ensure sensor cables are not run parallel to high-voltage lines or near motors, which can induce noise.
• Sensor placement: Confirm the sensor is fully inserted into the water stream or well and not partially exposed to air.
• Replace sensor: If readings remain unstable, replace the thermistor with an OEM Nirvana sensor.