Hello, I have yet another dreaded Hayward IF error. I feel like I have tested and replaced just about every component in this heater over the last couple years. This is a H300FDN that is about 11 years old. I replaced both control boards two years ago. So far I have verified the Ignitor is getting power and glowing hot red. Checked and cleaned the gas orifices on the manifold. Checked voltage to the gas valve, currently at 23.8 being supplied for a few seconds when attempting to fire. Gas pressure on the INLET side of the gas valve is 8", doesn't change at all when the valve clicks on. I am not seeing any reading on the MANIFOLD side of the valve. I haven't checked the flame sensor, but am planning to do that this afternoon. At this point I feel like it is leaning towards the gas valve needing replacement, but I wanted to see if I am missing anything.
Thank you!
Thank you!
