Coalgun- Puff backs & Explosions

Seems practical! As long as they don't over-design it and leave us with the choices of advancing and retarding the timing in order to have the spark plug firing before the fire reaches top dead center of the draft port door, at top dead center of the draft port door, or below top dead center of the draft port door.

It then becomes an internal combustion engine if you put wheels on the stove. The EPA will say well you could put wheels on it so they will regulate it. Ah, you say, it's a stationary engine so not federally regulated. That did not stop them banning a 1200# Lister diesel generator. Once the liberal lunies start there is no end. Perhaps they will think that you could strap wings on it then it's a plane and start looking at it's carbon signature and could it threaten the bird population. Environmental studies will be commissioned to study this. Stupidity absolutely knows no limit. Lala land is a wonderful place. Lewis Carroll could write books about obummerland.

that made my day

After about 10 days with no puffs (that I'm aware of at least), I've had two of them (so far) today. I topped the hopper off with 160 lbs. of fresh Harmony pea early this morning. Due to the cold weather the draft is excellent today, and the damper is routinely opening at 0.05", so draft does not appear to be the issue today. The last of my two puff backs today actually occurred while the fan was still running. The first one was not observed, but was inferred by sulfur smell upon returning home after being out this morning (after loading the hopper).

In my case at least the phenomenon now seems to be somewhat related to cold (as in 46 degree garage temperature) fresh coal from pails being introduced into the hopper.

All of this with my SV at a very low 105 degrees, and my hysteresis at 5 degrees.

your not the only one

dchartt wrote:your not the only one

Are you hearing puff-backs? What coal are you burning, and what are your current settings?

I just had my third puff-back of the day, and this one was the whopper of the day. This one happened when the fan cut off. Currently gettign a steady draft at 0.03" inches of water column (verified by placing the manometer hose on alternate sides of the manometer and getting the same reading on each side, sans for positive/negative sign). It's getting to be as bad as for back when my SV was at 130 degrees and my hysteresis was at 10 degrees.

Larry, any idea what your next adjustment will be to try and get the boiler to quit "woofing" at you?

Rob R. wrote:Larry, any idea what your next adjustment will be to try and get the boiler to quit "woofing" at you?

I just emailed Darren at AHS. I likely won't hear from him until tomorrow, or perhaps even until after the New Year. I'm running out of ideas.

Have you checked the fire height today? How does it compare to the days when you had no puff backs?

Bob wrote:Have you checked the fire height today? How does it compare to the days when you had no puff backs?

Good point. I'll have to look at it after the next heat cycle. Somewhat concerned with placing my face if the line of fire though.

I wonder why something changed after 10 days of cruising along nicely. And then I wonder what it was that changed....

lsayre wrote:

dchartt wrote:your not the only one

Are you hearing puff-backs? What coal are you burning, and what are your current settings?

mix of Reading pea and buck, 110 with a 5 deg hys.

it was kinda weird I made a big no no and didnt put the hopper lid back on the prior day and when I went to the barn to check on the boiler I noticed it, the fan shut off and woom, coal was pretty low in the hopper, looked inside the pot and there was a little fresh coal on top the fire but not much, it jammed my baro open

Larry, any idea what your next adjustment will be to try and get the boiler to quit "woofing" at you?

I think my next adjustment would be a Keystoker or a LL 110 or 220 if needed.

Kevin

KLook wrote:

Larry, any idea what your next adjustment will be to try and get the boiler to quit "woofing" at you?

I think my next adjustment would be a Keystoker or a LL 110 or 220 if needed.

Kevin

My AHS buddy Charlie found he had fewer puff backs if he kept the hopper near full and added a bag of coal each day, rather than add 5 or 6 bags once a week.

My AHS buddy Charlie found he had fewer puff backs if he kept the hopper near full and added a bag of coal each day, rather than add 5 or 6 bags once a week.

Then you are indicating air infiltration through the hopper. I thought they had lids on these things to prevent that?

Kevin

I still think the problem has something to do with ash build up or coal dust in the funnel of the boiler. Some of the wood gun users are compaining about puff backs and the only thing that would be similiar is the exhaust funnel of the two machines.

I emailed Darren pictures of my last explosion over a month a go and have yet to hear anything. I think they read the posts more than you think and from a legal standpoint they will not comment. The only way to stop the puffbacks is a complete design change that would increase the cost not to mention the length of time for the UL certification process.

If I could get a new EFM that would put out 260,0000 BTU to heat my shop and home the S260 would be back in Chambersburg at the AHS dock!

We should start a Baro- flue poll and see how many users have replaced flue pipes and Baro units over the puff backs. If your fridge would go in defrost mode every month or two and ruined your food. Or if your stove would just burn a $35.00 ham or turkey for no reason would you put up with it? Yet we continue to use an appliance that we paid big $$$$ for blaming the coal, draft or the operator for the explosions we have encountered. Man vs the machine....

Not to get off the subject but, I knew a car dealer that was a real overpriced rip off that would continue to have repeat customers . I asked him why the same customers would keep buying cars off him after he would give them nothing for the trades. Also all the cars were always priced way above book value? His answer . "They keep comming back hoping to get even on the next one!" I guess every ton a coal is a challenge!

Mac