so, the issue is really only of a single symptom: the igniter will not fire the propane when only on 12v battery power.
The fact that 120v power is somehow allowing the igniter to fire the propane is confusing, since it has no direct correlation or connection, BUT, could the Converter somehow be a clue?
It is the only thing that links the two, providing the conversion of 120v power down to 12v power.
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