Confirm the spa is supplied with power by looking at the power indicator light on the spa's control panel. The indicator light should be on. Check the spa's circuit breaker and ground fault interrupter if the indicator light is off. A flashing indicator light indicates that the heater temperature has reached its high limit cutoff. This condition can result from the circulating pump's filters being clogged. Cleaning or replacing the filters will reset the heater control to normal operation.
Determine if the display is locked by looking for the lock symbol in the display's lower left corner. The display is locked if a lock icon appears.
Unlock the display by simultaneously pressing the buttons marked "LIGHT minus (-)" and "TEMP minus (-)." The lock symbol will turn off and the display will be unlocked.
Determine if the temperature lock is activated by looking for the temperature lock display. The temperature lock is engaged if the word "TEMP" is displayed to the left of the water temperature display.
Deactivate the temperature lock by simultaneously pressing the buttons marked "LIGHT plus (+)" and "TEMP plus (+)." The word "TEMP" will turn off and you can adjust the spa's temperature.
Press the buttons marked "TEMP plus (+)" to raise the spa's temperature setting. The currently set temperature will be displayed, and will increase one degree each time you press the button until 104 degrees is reached. Continue to press the "TEMP plus (+)" button to obtain a spa temperature greater than 104 degrees. The temperature readout will then read: ut1, ut2, ut3 and ut4 with each setting being progressively warmer and ut4 being approximately 106 degrees.