If the unit won't start it is obviously not a real overspeed condition.
Before I did ANYTHING I would call Generac's tech support. Especially for such a new unit.
I had a similar condition on a 25Kw Winco and it was a bad ground in the alarm/sensor circuit.
I must say, one of the reasons I steer folks away from Generac is their poor customer service.
Do us (me) a favor and let us know how it turns out. I am curious to hear.
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