WFCO 1000 watt inverter

[Ddubya]

The WFCO inverter in my fiver runs Without or with shore power. I am guessing it is the fan. But why would it run with shore power connected?

[MattHelm21]

Unfortunately I don't have the answer but I can say that mine operates this way as well as long as I have the 12 volt disconnect for it turned on. If I turn the disconnect off the inverter will pass through the AC without the fan running but of course if power is lost then the fridge goes off. The funny thing is I don't think I noticed this behavior over the winter. I wonder if there is a temperature sensor inside which just runs the fan if over a certain ambient.

[Ddubya]

Ok, I called The WFCO people and they said that the inverter would continue to run with shore power attached. He said to just turn it off if I did not want it to run.
Seems like a pretty easy mod to turn it off automatically when shore power is applied and back on when power is removed. Another project when I get home.