Coalgun- Puff backs & Explosions

Re: Help: I Have Repeated Explosions!!

PostBy: Yanche On: Mon Nov 07, 2011 3:45 pm

lsayre wrote:Did the Coal Guns made 5 years and more ago have the 3/4" port hole in the sight tube cover plate?

My AHS S130 is a 2004 model, non thermal ash, with a simple timer motor grate controller. It originally had a solid view port door and solid steel bar went across the front to limit travel of the flapper during puff backs. The trick to get some air flow with the flapper close was to use a paper clip on the sheet metal, keeping the door somewhat ajar.

I now have the new tombstone cover and the flapper door with adjustable opening. Much better design and it has eliminated my puff backs.
Yanche
 
Stoker Coal Boiler: Alternate Heating Systems S-130
Coal Size/Type: Anthracite Pea

Re: Help: I Have Repeated Explosions!!

PostBy: rychw On: Mon Nov 07, 2011 8:22 pm

I have had my AHS 130 for 6 years and have had booms each heating season. My chimney drafts very well and have used a variety of coal from different companies without any success in eliminating the booms. I have tried a barometric damper and it has blown apart due to the blasts. I now have sealed stainless stove pipe without a damper. I have my ash dump temperature set at 120 and agree that the blasts occur when the grate operates and allows "fresh" coal to enter the burn chamber in too great of a quantity. I intalled the device to allow air through the flap and have it open 50%. I noticed that the new AHS boilers have a door covering the flap and the electric relays have been moved to the back of the boiler away from the flap. My fear is that one of these explosions will seperate my stove pipe or damage my chimney. My friend has experienced substantial chimney damage from an explosion with his AHS 130. There needs to be a solution offered by AHS since this is an ongoing problem that all of us AHS owners are experiencing. I don't buy the poor coal quality and chimney draft excuse. The new owners have also replaced the Fuji ash control with another type. I'm happy with the boiler perfomance but am very concerned about my family's safety. Any comments are appreciated.
rychw
 
Stoker Coal Boiler: AHS 130
Coal Size/Type: Pea
Stove/Furnace Make: AHS
Stove/Furnace Model: 130

Re: Help: I Have Repeated Explosions!!

PostBy: Rob R. On: Mon Nov 07, 2011 8:42 pm

Do you have plenty of make-up air available to the boiler?
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Other Heating: Dad's 1953 EFM Highboy

Re: Help: I Have Repeated Explosions!!

PostBy: rychw On: Mon Nov 07, 2011 9:15 pm

Yes, plenty of air available. My ash controller can't be set below 120 due to programming by AHS. I wonder if a lower ash temp would help prevent the explosions. Has anyone tried lower or higher ash dump temps in order to eliminate the explosions?
rychw
 
Stoker Coal Boiler: AHS 130
Coal Size/Type: Pea
Stove/Furnace Make: AHS
Stove/Furnace Model: 130

Re: Help: I Have Repeated Explosions!!

PostBy: watkinsdr On: Mon Nov 07, 2011 9:39 pm

Double check how your flapper door is operating. My ka-booms ceased after loosening the flapper door such that it always releases when the boiler fan stops running---it cannot stick now. My most recent S260 ka-boom was caused when too much draft kept the flapper door sucked up against the sight tube (even with the rotating door open). I discussed with Darren at AHS---he recommended loosening the flapper door significantly to ensure fresh air is always pulled across the fire bed, exhausting excess gas volatiles when the fan stops running. Sounds good in theory; and, I haven't had any explosions since loosening the flapper door... Double check your baro damper too if you're using one... Clean out any residual fly ash; and, lubricate the pivot points with some 3 in 1 oil.
watkinsdr
 
Stoker Coal Boiler: AHS S260 Boiler

Re: Help: I Have Repeated Explosions!!

PostBy: McGiever On: Mon Nov 07, 2011 9:48 pm

So, AHS doesn't see it necessary to have this kind of info. in their manual...they wait till you call after you have had an explosion or three and call up saying WTF... then they give you the solution. Ooookay :!:
McGiever
 
Stoker Coal Boiler: AXEMAN-ANDERSON 130 "1959"
Hot Air Coal Stoker Stove: HARMAN MAGNUM
Hand Fed Coal Stove: RADIANT HOME AIR BLAST
Baseburners & Antiques: OUR GLENWOOD 111 BASEBURNER "1908"
Coal Size/Type: PEA / ANTHRACITE, NUT-STOVE / ANTHRACITE
Other Heating: Ground Source Heat Pump
Stove/Furnace Make: Hydro Heat /Mega Tek

Re: Help: I Have Repeated Explosions!!

PostBy: Rob R. On: Mon Nov 07, 2011 9:57 pm

rychw wrote:Yes, plenty of air available. My ash controller can't be set below 120 due to programming by AHS. I wonder if a lower ash temp would help prevent the explosions. Has anyone tried lower or higher ash dump temps in order to eliminate the explosions?


At some point I think you would be risking a hopper fire...there is a reason they don't want the ash setpoint below 120 degrees. Try admitting more air over the fire.
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Other Heating: Dad's 1953 EFM Highboy

Re: Help: I Have Repeated Explosions!!

PostBy: Bob On: Mon Nov 07, 2011 10:00 pm

rychw wrote:Yes, plenty of air available. My ash controller can't be set below 120 due to programming by AHS. I wonder if a lower ash temp would help prevent the explosions. Has anyone tried lower or higher ash dump temps in order to eliminate the explosions?


If you have the Fuji controller it can be programed so that the temperature can be set lower. SV-L is the low temperature limit in the instructions. Set it to, for example, 115 and then you can set the grate down to 115.

But exercise caution in going below 120--as you reduce the grate setting the fire moves up in the column and my experience is you want to be able to see it but not much above the bottom of the port.
Attachments
AHS Thermo grate programmingl.pdf
(67.1 KiB) Downloaded 7 times
Select:BBcode: [nepafile=30669]AHS Thermo grate programmingl.pdf[/nepafile]
Bob
 
Stoker Coal Boiler: AHS 130
Coal Size/Type: Pea/Anthracite

Re: Help: I Have Repeated Explosions!!

PostBy: whistlenut On: Mon Nov 07, 2011 10:25 pm

If you tightened the observation door nut too tight(spring compressed, too), that could be another cause for the 'big bang theory'. Some folks just don't understand that some free play is designed into the system, and most AHS units are not a problem. The Fugi controller is easily adjusted to lower grate temps, but don't get toooooooo damned smart and think you can re-invent the wheel. Many smart folks have been down this road long before you and I; appreciate it, and back off on the panic situation. If you have issues of shaking like a fairy at a weenie roast, then re-thing the whole coal situation. Personally, I hope you become very adept at running that fine unit, and the comfort you and your family enjoys will make this small issue something to laugh about later.

I did the first 'Big Bank' in 1972 with two AA260's, and I learned to respect off-gasses from whatever source. Heck I visited a friend that was spraying Lacquer Paint with a hand fed stove roaring away.......that had my knees knocking and heading for any opening in the building before it became a test explosion. Yup, it scares you until you understand why it happens...reaching the lower explosive limit from off gasses equals a bad noise and projectiles flying if not secured in place...... :idea: :!: :shock:
whistlenut
 
Stoker Coal Boiler: AA130's,260's, AHS130&260's,EFM900,GJ&VanWert
Hand Fed Coal Boiler: Franks Boiler,Itasca415,NYer130,Van Wert
Hot Air Coal Stoker Furnace: Yellow Flame
Hot Air Coal Stoker Stove: Alaska-4,Keystoker-2,
Hand Fed Coal Stove: Alaska,Gibraltor,Keystone,Vc Vigilant 2
Hand Fed Coal Furnace: Van Wert, NYer's, Ford,Jensen.
Coal Size/Type: Rice,Buck,Pea,Nut&Stove
Other Heating: Oil HWBB

Re: Help: I Have Repeated Explosions!!

PostBy: Freddy On: Tue Nov 08, 2011 5:06 am

lsayre wrote:the puff-back trouble is generally related to both the quality of the coal


Maybe, but I personally am thinking that "the better" the coal, the worse the booms. I am burning Superior deep mined coal. (I understand the deep mined is no longer available). It has more heat per ton than most (all?) coal. I'll tell ya, I have had some record breaking booms! I honestly think it's because my coal has more energy in it than surface mined coal. Just this week I received a new manometer to replace the one that my last boom blew apart.... not barometer...manometer! As long as I have my anti boom device turned on I do not have booms. It's a home made device that holds the view port door open for ten seconds at the end of each burn. I use it in the Spring & in the Fall. During the dead of winter the coal bed doesn't get deep enough I guess.
Freddy
 
Stoker Coal Boiler: Axeman Anderson 130 (pea)
Hot Air Coal Stoker Stove: Reading piece o' junk in the barn (rice)
Coal Size/Type: Pea size, Superior, deep mined

Re: Help: I Have Repeated Explosions!!

PostBy: rychw On: Tue Nov 08, 2011 7:31 am

Thanks for everyone who has offered thier opinion and help with the booms. I had two more last night while in bed so I had a very restless night. I have the the flap adjusted to open immediately after the fan cuts off so that isn't the problem. Again both booms occured with the grate moving and ash dumping while the fan just cut off. I'm calling AHS today but not confident they will offer a solution different from the forum thus far. The boiler was completely cleaned a few weeks back and there is no fly ash in the stovepipe. I'll adjust the Fuji controller to dump at 115 today and watch the hot coal level closely.
rychw
 
Stoker Coal Boiler: AHS 130
Coal Size/Type: Pea
Stove/Furnace Make: AHS
Stove/Furnace Model: 130

Re: Help: I Have Repeated Explosions!!

PostBy: Rob R. On: Tue Nov 08, 2011 7:56 am

rychw wrote:Thanks for everyone who has offered thier opinion and help with the booms. I had two more last night while in bed so I had a very restless night.


I would be frustrated as well. One thing you haven't mentioned is draft...have you ever checked the draft while your boiler was sitting idle at operating temperature? What temperature do you normally operate the boiler at?

All coal boilers have their pros/cons, but chimney damaging explosions in the basement is more than I would be willing to deal with. If there are any women in the house I hope they are understanding and you are able to get this resolved soon.
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Other Heating: Dad's 1953 EFM Highboy

Re: Help: I Have Repeated Explosions!!

PostBy: MATTHEW D. On: Tue Nov 08, 2011 8:11 am

This is verbatim from the axemzn-anderson 130 manual. " While pea size coal is recommended, the unit will operate very well on Buckwheat size coal which is smaller. However, it is necessary on the 130m unit to remove the 5/8" plug in the sight cover when burning buckwheat coal to allow additional air to enter to prevent puff back. Due to the more compact fuel bed the gasses cannot always flow properly without this excess air. If the 130m is an older model without the sight cover plug simply drill a 5/8" hole in the sight cover." I had a few puff backs with pea. I am currently burning Buck, it eliminated my outfire problem in the summer. May be this can help? Here is a pic of my sight cover with the plug out
Attachments
100_8157.JPG
(141.31 KiB) Viewed 8 times
View: New PagePopup • Select:BBCode
[nepathumb]30684[/nepathumb]
100_8153.JPG
(117.93 KiB) Viewed 7 times
View: New PagePopup • Select:BBCode
[nepathumb]30685[/nepathumb]
MATTHEW D.
 
Stove/Furnace Make: AXEMAN-ANDERSON & EFM
Stove/Furnace Model: 130 & 900 x 2

Re: Help: I Have Repeated Explosions!!

PostBy: rychw On: Tue Nov 08, 2011 8:25 am

I'm burning pea and my draft at idle is good.

Yes there are women in the house and it is getting increasingly difficult to keep the boom concern under wraps. At this point there appears to be a correlation between the booms and the ash dumping while the fan is off or just shutting off.
rychw
 
Stoker Coal Boiler: AHS 130
Coal Size/Type: Pea
Stove/Furnace Make: AHS
Stove/Furnace Model: 130

Re: Help: I Have Repeated Explosions!!

PostBy: Rob R. On: Tue Nov 08, 2011 9:21 am

Does the ash controller have a differential setting?
Rob R.
 
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Other Heating: Dad's 1953 EFM Highboy