I replaced the hot surface ignitor in my friend’s Rheem gas water heater. The one I replaced had a crack in it so it wouldn’t even light the burner. Once the new one was installed, I turned the unit on and watched it glow and ignite the burner. However, my friend says that the tank has been getting cold on her periodically. She has to cycle the power on the unit to get it to re-start and ignite the burner. When she approaches the unit to reset it, the power-vent fan is running. Can anyone tell me where to go next? Is there a flame sensor that may have failed or could it be the gas valve or the ignition board?
Thanks,
Eric Hayes