Jandy Model LJ Natural Gas heater, FL4 ignitor failure code

[bob22]

Daughter's ~10 year old heater is showing a FL4 service code. It had been running for a number of times in prior weeks.

FL 4 (igniter) code and steps from manual:

1. Igniter circuit is open: Check fuses on igniter wires. Identify and correct loose connections or broken wires.
2. Element has a fine crack in it: Measure room temperature resistance and ensure value is in the correct range. See manual for details.
3. Igniter fault: Replace igniter

She ordered new ignitor and after getting old one out (very rusted screws), I had her cycle the heater. The ignitor glowed fine. Plugged in the new one and same amount of glow.
Ohm meter on each ignitor was between 30 and 300 ohm (like 85 and 140).

Reinstalled old ignitor and she gets same service code and failure to ignite.

Any ideas on what to check next?

 

[ajw22]

Maybe @swamprat69 @ps0303 @1poolman1 has ideas.

 

[1poolman1]

If the wiring and ignitor are good, have to start susoecting the control biard.

 

[bob22]

That's my thought and it's an expensive one to replace on a 10+ year old machine since hard to determine how soon it might spring a leak.