hayward pool heater turns on and than right off

[bmanino]

I have been experiencing problems with an h series hayward heater. I turn it on and it goes on then shuts off about 5 seconds later. This happens every time. I have backwashed and even chaged the pressure switch.

[ozzzie3]

did you ever get the problem solved?

[Mike54]

I am having the exact same problem witrh my Hayward H series. It will fire up and then in exactly five seconds the flame quits. I still don't know what the problem is . Did you ever figure the answer to this ?

[Me...]

You might have an issue with your venting or exchanger being at least partially blocked. If the heater can't get rid of the products of combustion, excess heat and/or flames etc will roll out the bottom by the burner tray. There is a safety switch that will detect that and prevent the heater from firing.

Heater fires, switch then detects the problem a few seconds later and shuts it down. If it doesn't shut it down you will cook the wiring the gas valve other controls and worse. A much more expensive proposition than calling a gas fitter to check it and clean it if needed. They usually recommend a cleaning at least once a season.

It also could be either an internal or external bypass that is causing not enough water to pass through the exchanger. That would then cause the high limit to kick the heater out shortly after it fired.

I did this for years. Believe me, it's much cheaper to have a guy check and fix it now than what can happen if you don't.