I thought about that too but normally the furnace motor starts first when the thermostat calls for heat and then the air flow from the blower is proven by the sail switch connecting 12v through the limit switch to the control board to continue the gas light process etc.
One other option is what if the sail switch remains stuck in the blower prove position sometimes.......maybe the 12v being applied to the control board through the prove circuit before it should be is causing the issue.....but there are no codes shown. Then banging the side of the coach frees the sail switch to return to normal open position. For such a new coach you would not think the sail switch would even be a problem....famous last words.
__________________
|