My problem is (was) intermittent. The inverter is running perfectly (though the fan is bothersome) in the driveway right now. All day in fact.
Earlier this week though .... stayed at a park with high voltage (129VAC). The hardwired surge protector would not allow us to connect to shore power, until the voltage dropped below 128 V. Even then, the pedestal power was 124 VAC. I suspect the converter was over charging the batteries, since the battery voltage was 14.4 VDC, which is much higher than the optimal 13.7 VDC. The excessive battery voltage may have caused the inverter to stumble. The owners manual is not particularly useful, especially the troubleshooting flowchart. Their flowchart said "Replace the inverter"
I called Power Surge to see if there is a way to calibrate the high voltage limit and they said "NO". The engineer suggested buying a Variac or autotransformer to dial the shore power voltage down. We will test my intermittent failure theory once my Variac arrives since I can replicate the overcharge condition.