Safety: Turn off power before handling sensor wiring.

Inspect sensor plug: Reseat the Sta-Rite temperature sensor connector on the control board.
Check cable routing: Ensure sensor wires are not bundled tightly with high-voltage pump or light cables that can induce noise.
Test sensor resistance: Measure resistance at the board terminals and compare to water temperature. Replace sensor if unstable.
Replace harness if damaged: Install a new sensor harness if insulation is cracked or chewed.

Heater display shows erratic or jumping temperature readings without an error code

Possible Causes