Display shows Sn1, SN1, or SENSOR 1, spa may not heat or may shut down heater.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety: Turn off power at the breaker before touching any wiring or sensors.
- Locate the temperature sensor: In the equipment bay, find the sensor inserted into the heater tube or plumbing (usually labeled TEMP or SENSOR 1 on the control board).
- Check seating: Ensure the sensor bulb is fully inserted into its well and secured with the retaining clip or nut.
- Inspect wiring: Follow the sensor cable back to the Saratoga Spas control board. Look for cuts, chew marks, or pinched sections. Reseat the plug on the board by unplugging and plugging it back in.
- Compare displayed temperature: Restore power and compare the displayed temperature to an external thermometer in the spa water. If the reading is wildly inaccurate or Sn1 persists, the sensor is likely defective.
Replace the temperature sensor with a Saratoga-compatible thermistor. If a new sensor does not clear the error, the control board input may be faulty and require professional service.
Repair Difficulty
Required Part
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