Home Improvement Questions? Ask a Handyman for Answers
I'm sorry but I don't recall your inquiry. What's the brand and model of your unit?
I found the original thread. If you don't have voltage to the gas valve the gas valve is not the problem. You need to test the connections with a meter. A visual inspection is not adequate. FL3 & FL4 are both igniter errors. You might want to replace the igniter. You wouldn't get power to the gas valve with an igniter fault.
You need to check the connections and look for flaws in the igniter. Your pic doesn't show me much. Do not try to clean the igniter. Also wiring diagram shows fuses in the leads to the igniter.
Since you have a new board the igniter (maybe the fuses) is the most likely culprit.
All I know is that the wiring diagram shows a fuse in each igniter lead between the board and the igniter. Most likely old glass type automotive fuses.
Then your next step is to replace the igniter.
You're getting 2 igniter errors. So it's either the board or the igniter. There are no other possibilities
no way I can know that