My heater is working perfectly. My neighbor's is not. He's got a 2 year old Hayward H250FDN. It has worked 2 months so far this summer with no issue but in the last few days it's not been working. Here is what it does:
Water temperature displayed is 80.
Heater set to 85.
I can hear it ignite and burners fire up.
It runs for 10 seconds at most and shuts down.
Error code HF displays.
After a minute or two it begins again showing temperature and goes through the above steps again.
Occasionally we'll see an IF code but that's only been once or twice.
What I've done:
Cleaned ignitor (heater worked for 36 hours then same as above)
Replaced ignitor with new (did not fix)
Replaced gas valve (did not fix)
Checked and rechecked gas lines (did not fix)
Next up might be replacing the ICB? Before this all started he saw what he called smoke bellowing out from the back every time the heater fired. I didn't witness it but he mentioned it after the problem above started.
Any thoughts on what to try? The heater is barely 2 years old and he's frustrated that with what he's bought so far and an ICB purchase he's getting closer and closer to the cost of replacing the complete heater.