New member here. I have a Sta-Rite SR400LP heater that is around 4 years old and has operated perfectly until now. The unit has power and the blower does run but it won't fire. After the blower stops, it gives a Service Heater led and an AFS led on the underside of the board. Checked for obstructions and damaged wiring and everything looked good. Ordered a new AFS switch with new tubes and installed it last night. Tried it again and I'm still getting the same symptoms and error led's.
I'm assuming the next logical step is to replace the Control Board (p/n 42002-0007S) ???
Any help would be greatly appreciated!