Spa heats but overshoots the set temperature by several degrees before shutting off.

Safety: Overheating water can be hazardous. Monitor temperature with an external thermometer.

• Step 1 – Verify with thermometer: Compare displayed temperature to an accurate external thermometer placed in the spa water away from jets.
• Step 2 – Check circulation: Ensure the circulation pump is running properly and that all diverter valves are open enough to move water past the heater and sensors.
• Step 3 – Sensor replacement: If the display is inaccurate or slow to respond, replace the temperature sensor on the heater tube.
• Step 4 – Relay evaluation: If the heater indicator remains on even after the set temperature is reached, the heater relay may be sticking and the control pack should be serviced or replaced.