I came home from lunch yesterday and walked by our volvo sitting onside our house and heard the radiator fan running. I though that it was odd, as I don't ever remember the radiator fan staying on after shutting the car off. Is this normal behavior? It was about 80 degrees out. Normal weather, not normal car behavior.

So later my wife calls and says the car battery is dead. And she said she too noticed the fan running.

My conclusion - fan draining battery. So she jumps the car and returns home. No fan running this time. Car re-starts. She uses the car that night - on a longish drive - 20 minutes each way. No problems.

In the morning - dead battery.
Oh, BTW the battery is relatively new - about a year old.

So my question is this:
Is the fan-on thing normal or should I investigate that before trying to track down some other battery drain/electrical problem?

Thanks a million!
Jamie.