Well, I figure this is a good place to tell on myself. I had a little mishap last night. I'm still not exactly sure the order of events, but I will do my best to summarize. I went out, opened the door and shifted around the coals and remaining pieces of wood, as per normal. I threw in 2 pieces of wood toward the back. It started to smoke a bit, so I turned on the fan by adjusting the thermostat to call for heat. Again, as per normal. So, the fan kicked on, changed the smoldering into a fire on the remaining wood, and the thick smoke thinned out, as per normal.
Now, this is where things get fuzzy. I think, for some reason, I closed the door. I'm really not sure why I did that, but I think at that point, the fire extinguished, even though the fan was still going. A few seconds later, I hear a WOOSH, and flames came out of the chimney! I was a little startled as a 10' flame erupted and continued to burn out the top of the chimney. See attached picture. But, that wasn't the bad part. What I didn't know, was that the WOOSH had re-extinguished the fire. The flame was just the creasote burning off the chimney. So, I turned off the fan and went to open the door. When I opened the door, I saw how pitch black it was inside. At this point, the exact course of events is a little fuzzy. I didn't black out, but the adrenaline dump must have erased my memory. I remember seeing how black it was inside, I remember thinking "not good," then I remember the biggest WOOSH and fireball I have ever seen! It was so strong that the water gauge right next to the chimney was sucked out of the stand pipe and fell to the ground!
Somehow, with the fan, the smoldering, the wood gases, the fire going "out" and the door opening had created the perfect storm for a massive backdraft! I think I lucked out. No singed hair, no stove damage, no fan damage. A new pair of underwear and I was good to go!
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