Short cycling Hayward H100ID1 natural gas pool heater

[yelleklleb]

I recently replaced the heat exchanger in my Hayward H100ID1 1000 BTU natural gas heater I have used for over a year to heat my 850 gallon in-ground spa. Prior to replacement (I was quite sure the exchanger was leaking,) the unit would light automatically only to shut off in ~10 seconds and after igniting 2 or 3 more times, the controller circuit board would offer the 3 flashes on the red status led.

Per the manual, after about an hour in this alarm mode the unit would restart the cycle.

I have jumpered around all sensors in attempt to troubleshoot but no help. The thermostat switch is operable as this allows me to reset the error indicator and initiate a relight sequence by turning dial down and back up to normal setting around 100 F. Likewise the pressure switch is working as it should. I cannot confirm the status of the two overtemp sensors on the exchanger but since water is only 78-80 F they should not be an issue.

Any help around this subject would be appreciated.

 

[kimkats]

Way beyond my pay grade but here is a bump to get it in front of more eyes.

 

[ps0303]

Your ignitor/flame sensor is bad. When your unit lights and then goes out and then does it again and a third time, it is usually the ignitor. This part is also the flame sensor and when it doesn't sense the unit lit, it doesn't complete the cycle to allow it to keep burning.