Note to self; when removing ash buildup from firebox, make sure to leave enough coal behind to rekindle fire. This morning when I went to put wood in the OWB it had quite a bit of ash buildup. it's depth was making me uncomfortable so I removed some of it. I guess in the process of taking it out I took out too much coal at the same time. I was doing some reading in my reading room and I heard the oil burner come on. That meant one thing. So I went out and sure enough the digit display was flashing FO, fire out with a water temp approaching 150. Upon inspection, yup, the fire was out and no hot coals anywhere. So, remove the unburned wood, put in a huge pile of kindling, touched it off and then held the primary air switch in to really get her going. After a few minutes, I added a few pieces of unburned stuff and the water temp is rising nicely now. The oil burner is quiet too. Roger