This Control Thermostat Thermistor communicates the actual water temperature to the controller to shut off the heater when the spa reaches target temperature. It is used on all 2006-current Hot Spot Mallorca, Sorrento, Trinidad & Tobago spa models. It is also used on all 2006-current Solana RX, SX & TX spa models. Used on the 2009 forward Hot Spring.

Test Procedure

1. Set the meter to 20K on the OHM scale.
2. Record the temperature of the spa water.
3. Unplug the thermistor from the control box.
4. Meter across the two Thermistor leads.
5. Refer to the Temperature versus Resistance chart below to find the correct resistance value for the temperature measured. If the temperature and resistance does not match that of the chart, this test has failed and the thermistor must be replaced. Remember if the spa has been inactive, the spa water temperature may be different
than the water temperature in the heater housing.


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