Hayward H400FDN Natural Gas won't ignite

MNAL

New member
May 7, 2009
4
Hey everyone-

I am at a loss with my situation and looking for some help. I bought a brand new Hayward H400FDN natural gas heater about a month ago. Installed it and it fired up just beautifully. Ran for probably 5 hours and went out. Could not get it to light again the rest of the day. It would try to light 3 times and then give me the IF error. Waited a few days and did some reading online and saw some people were covering the blower fan half way with tape, so I gave that a shot. Fired right up and ran for another 4-5 hours and shut off. Again, it would attempt to light the 3 times and IF out.

I waited till the weekend and took the gas line out of the unit and made sure there was no water/debris in the line. Even vacuumed out where the line attaches to the unit. Nothing. Had friends coming over the next day and magically it light that morning, but again for only maybe 5 hours. It has been over 1 week and I can not get it to light at all now. I removed all the gas orifices and made sure they were clear. The unit only being 1 month old, they were all clear as day.

Again, the unit is brand new. 1 month old and I have only been able to have it run 5 or so times total(run times vary from 1-5 hrs). It is a natural gas unit if that makes any difference. I am planning on going to measure voltage across gas valve right now.

Any ideas?
 

markayash

Gold Supporter
Mar 21, 2016
549
Marrietta Ga
Just a thought when I installed mine I had issues and had the natural gas folks come out and they found the flexible tube I reused was twisted and limiting gas flow.
 

MNAL

New member
May 7, 2009
4
I had thought about that, but when I put this one in I literally replaced a old unit at the union.... The whole run is copper or black iron pipe, no flexible anywhere. Our gas line is buried 100+ feet from where it splits from our meter so I am really dreading that possibility.

To me it doesn't make sense that it will work sometimes just fine for hours and then 90% of the time I get noting. I would think if it were a line/supply issue it would just not/never work?
 

markayash

Gold Supporter
Mar 21, 2016
549
Marrietta Ga
That is weird, mine would lite some and i had reused the old flex pipe. i called Atl gas light out he heard it whistling and actually replaced it for free.
Did you make sure the thermocoupler is tight at the valve? If you look in the opening does it lite and go back out?
hayward wanted to charge me to come look at it when my control board failed. New board was about the same price as the service call. Had a lot of issues but seems stable now. I did make a tarp to cover the control board ;)
 

swamprat69

Active member
Mar 30, 2019
36
Las Vegas, NV
If it runs 4-5 hrs. when it is a cold start and then won't run even though you have not gotten to the temperature that you set, it would seem to be an over temperature safety problem possibly due to a restricted flow or temperature sensor. If you can find where you are losing the circuit with a multimeter when it won't run, it would help to isolate where the problem is.
 

CPS Reno

In The Industry
Feb 6, 2019
30
Reno, NV
We've found "most" of the issues like this need a manometer. Without that, you're basically guessing until you stumble on the solution. You can buy decent manometer's on Amazon for $30. Worst case scenario is that you confirm that you're adjustment is correct and eliminate the gas flow as an issue.
 

ps0303

TFP Expert
In The Industry
Jul 6, 2011
4,006
FL
Have you considered calling a local company that services Haywards?