Goodman

8 flash

Lockout

IGC 8-flash — example

Example: internal control / valve circuit on current CES rooftop stickers. Power-cycle once; if 8-flash returns, valve ohms then IGC.

Walk 8 flash in Diagnose

2 plates — walk the one on the cabinet

First check

1 Ohms at the igniter, then at the IFC

On Goodman GMSS96 measure cold ohms at the igniter plug, then at the IFC connector. An open at the plug is the element or local harness. Open only at the IFC is the harness rub-through on the collector. Ohms at the igniter, then at the IFC.

Expect: Nitride cold ohms per THIS door sticker — do not use an 80% Norton chart.

The rest of the walkthrough is Diagnose.

On the plates

Ohms at the igniter, then at the IFC.
120 VAC during warm-up. Nitride, not an 80% Norton chart.
24 VAC at the valve during a known trial. Coil ohms vs the valve sticker.
A 8-flash that clears on a power-cycle and never returns was a glitch. Repeating 8-flash is a part.
Do not keep swapping IGCs before you measure the valve.

Plates that use 8 flash

Same number, other makers

8 flash on Goodman is not the same code on these plates.