Most pool heaters offer an automatic ignition system and monitor the pool water temperature to maintain the temperature as set on the thermostat. The heaters vary in heat output, usually between 92,000 BTUH and 133,000 BTUH and can be turned up or down according to pool-temperature needs. The unit also has a temperature limit switch that will trigger an automatic lockout if the temperature is exceeded during ignition. Troubleshooting this problem may help prevent the ignition lockout from happening in the future.
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.