Reset the circuit breaker to reset the pool heater and the ignition-lockout system.
Check the water flow through the pool heater to ensure nothing is obstructing the water flow, which can affect ignition and temperature monitoring. Clean the filter-pump strainer and the filter.
Lengthen the running time of the pool-heater clock to a 24-hour operation, as the unit may shut off before the desired temperature is reached if the thermostat is set to a high level. Manually turn the timer-override switch if necessary, to turn the pump back on.
Set the pool-heater thermostat above 60 degrees F and less than 105 degrees F -- to prevent temperature excesses that might cause the ignition lockout.
Use the pool cover when the pool is not in use, as ambient temperatures can affect the pool-water temperature by more than 10 degrees F, triggering the ignition lockout if the temperature is too low or too high.
Access the main-control panel on the heater, which may require removal of hair-pin clips to access the control-board dome. Press the “Max Temp Set Point” button or key pad, and then press the up or down arrow to turn the maximum or minimum ignition-temperature set point up or down. The temperature should be between 60 and 105 degrees F. Push “Set” if applicable, and then close the cover over the control panel.