ScottG wrote:
The battery level indicator lights are nearly meaningless because when a hi load item (like a water pump) comes on the voltage in the line drops.
It's possible the pump motor is badly worn and drawing too much current but not very likely. I suspect your battery is still not up to the task. I would make sure the converter is working properly and the battery is getting fully charged.
But the voltage indicator lights going off as another load is turned on is normal.
X2
Although you said,
"we couldn't' power our led lights and our water pump at the same time. We could run the furnace and lights though."
In that old of a rig, I suspect the pump is bad & your battery is being drawn down very rapidly in attempting to use the pump.