Backdraft Bang!! Econoburn 150

[wantstoburnwood]

I have had a back draft bang 3 times recently. It seems to only happen when the boiler is cold ( no fire for 24 hrs) . When I light it I let the fire heat up with my ash chamber door open and the damper wide open. When I shut the damper and turn the fan on that is when I get the bang. Does anyone know how to prevent this??

 

[Dave T]

Not for sure on this but if you have triple wall pipe check the clean out plug in the bottom make sure it is seated and clamped..Dave

 

[Nofossil]

Here's my theory: when you close the top door and the damper, you immediately get a top chamber full of combustible gas at very high temperature. When the fresh air from the blower comes in, you get a bang, then it settles down.

I haven't had that problem in years, so I'm a little fuzzy on what I did (or stopped doing) that solved the problem. However, I think it's most likely a result of too much really small / really dry wood used to start the fire along with waiting too long to switch over to gasification.

 

[Grover59]

My boiler is different, however I have had this problem but, I agree with nofossil the small wood and all of that smoke that will flash once you put the air to it. I start my blower first with the bypass damper open, then I drop the damper I generally get the gasification without the bang.

Steve

 

[Medman]

I had the same thing happen with my first few fires. Now I close the bottom door, start the fan, wait a few seconds, and then close the bypass damper. It gives the fan time to move the smoke/gases to the bottom chamber before the damper closes. I haven't had the problem since, with no change in the wood load.

 

[wantstoburnwood]

I got her lit this evening without any bangs. Thanks everyone for your input.

 

[ebbci05]

I get the same thing once in a while. I get it when I have the gasification door open and the top door closed to help start the fire. When I close the bottom door and turn the fan on, it "bangs" I have found that it helps if I leave the top door open a little while the bottom door is open. not too much because then the smoke comes out the door, just an 1" or so. Once the starter fire is roaring, I turn up the temp which turns the fan on. I try to close the bottom door the same time the fan comes on. Once the fan is on the fire continues to burn but pushes most of the excess gasses out the chimney. I then can close the top door and close the damper for gasification, without a bang. Without the top door open a little, helping suck in fresh air, I almost always will get a backdraft situation(mostly b/c I don't want to wait and let the fan push all the excess gas out b/f closing the damper for gasificaiton)