Well, I've been burning sub-bit in my Vogelzang Norseman stove "basically a hotblast" for a couple of years now and have had really good luck. I've had a few puffbacks but haven't had one for almost a year now until the other day... It all started when I woke up and the house was a little cool which was strange as I have built a damper that is thermostatically controlled that controls the temperature of the house. I went downstairs to investigate and make sure the damper was open. To my surprise it was. I then opened the stove door to see what was going on in there and saw that a large chunk of coal had not burned much. It just looked like the grates needed to be shook a little and all would be well. I then proceeded to close the door and then I gave the grates a couple of shakes and closed the ash door. I saw that I had some coal crumbs on the floor in front of the stove so I swept them up and then stood up to go back upstairs. I started walking towards the stairs when "BOOM". It was like a shotgun had went off. The barometric damper flew out of the stove pipe and just missed my head and hit the wall about 12 feet from the stove. I looked at the stove pipe thinking that it was surely going to be split at the seams. Luckily it had not. I was sure glad I had all joints screwed with three screws. I then noticed that the ash door had been blown open and there was ash and hot coals everywhere on the floor in front of the stove. I quickly shoved the barometric damper back in and closed the ash door and then proceeded to sweep the hot coals close to the stove away from objects that could catch fire. Thankfully I'm very opinionated about keeping things well away from the stove that could catch fire. Thankfully, other than a huge mess and one ear that was ringing, all was well. This incident has put a little fear into me about burning coal. I thought about letting the stove go out but we were using it to heat our water as our tankless water heater had croaked and we haven't got a new one installed yet. This all happened a couple of days ago. I since have decided to keep burning coal. I will fabricate a more positive latch for the ash door and I will now screw in the barometric damper. The reason the baro was not screwed in is because I occassionally burn a little wood and I remove it then. I am really glad that I took my time to install the stove correctly and safetly and always kept things away from the stove. I'm not sure what would have happened if we were gone, but thankfully we were home.
I'm not trying to preach to any of you, but PLEASE do make sure your stove is installed correctly and keep ANYTHING that could possibly burn well away from the stove.
Ben