Puff backs in coal gun
- hotblast1357
- Member
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- Joined: Mon. Mar. 10, 2014 10:06 pm
- Location: Peasleeville NY
- Stoker Coal Boiler: 1984 Eshland S260 coal gun
- Coal Size/Type: Lehigh anthracite pea
- Other Heating: air source heat pump, oil furnace
Are you having puff backs?
If the fire is set properly there are no puff backs.
If the fire is set properly there are no puff backs.
- StokerDon
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- Location: PA, Southern York County!
- Stoker Coal Boiler: Gentleman Janitor GJ-5, Van Wert VA-600, Axeman Anderson130 X3.
- Hand Fed Coal Furnace: Harman SF3500 reduced down to 3 grates connected to its own plenum
- Coal Size/Type: Rice, Chestnut and whatever will fit through the door on the Harman
- Other Heating: Noth'in but COAL! Well, Maybe a little tiny bit of wood
Welcome to the forum.
This is the only "Freddy" that I know of on the forum. he has an Axeman Anderson though.
memberlist.php?mode=viewprofile&u=1789
You can send him a PM if you wish.
Getting the sight hole to pop open before the heat cycle ends probably isn't the way we would cure puff backs these days though.
Do you have one of the older Coal Guns that ash by a timer rather than ash temperature?
-Don
This is the only "Freddy" that I know of on the forum. he has an Axeman Anderson though.
memberlist.php?mode=viewprofile&u=1789
You can send him a PM if you wish.
Getting the sight hole to pop open before the heat cycle ends probably isn't the way we would cure puff backs these days though.
Do you have one of the older Coal Guns that ash by a timer rather than ash temperature?
-Don
- hotblast1357
- Member
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- Location: Peasleeville NY
- Stoker Coal Boiler: 1984 Eshland S260 coal gun
- Coal Size/Type: Lehigh anthracite pea
- Other Heating: air source heat pump, oil furnace
Like don is getting at, fire control is key.. the old way with a timer is no good...
Best way is to control ash is with a temp sensor, and ONLY ash when the fan is running.
I have not had one puff back. And I run a grossly oversized boiler that idles a lot, with 0 draft 90% of the time.
Best way is to control ash is with a temp sensor, and ONLY ash when the fan is running.
I have not had one puff back. And I run a grossly oversized boiler that idles a lot, with 0 draft 90% of the time.
- coaledsweat
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- Location: Guilford, Connecticut
- Stoker Coal Boiler: Axeman Anderson 260M
- Coal Size/Type: Pea
Stop ashing for a bit to raise the fire. Too much fresh coal on top.
Mine ashes by temp set at 135 plenty of coal built up for fire bed seems to do it on long runs sight hole is open now placed a thin washer at bottom of flap to keep a small amount of air flowing in while blower is running has not popped again it cycled on and off about 6 times over a 6 hour or little longer period of time
- StokerDon
- Site Moderator
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- Location: PA, Southern York County!
- Stoker Coal Boiler: Gentleman Janitor GJ-5, Van Wert VA-600, Axeman Anderson130 X3.
- Hand Fed Coal Furnace: Harman SF3500 reduced down to 3 grates connected to its own plenum
- Coal Size/Type: Rice, Chestnut and whatever will fit through the door on the Harman
- Other Heating: Noth'in but COAL! Well, Maybe a little tiny bit of wood
If it is Puffing back on a long run and not after shut down it may be ashing to much burying the fire. Lowering the ashing temperature may help and a little over fire air like you have added will help too.
-Don
-Don
Yes it puffs back after a long run at shutdown. Making my wife very unhappy can't blame her. I leave the cap on the T above the hopper loose so it blows it off and doesn't blow the flu pipe apart. People from alternate heating are no help .
- coaledsweat
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- Stoker Coal Boiler: Axeman Anderson 260M
- Coal Size/Type: Pea
You should see a ring of fire breaking through the raw coal or about to at the surface along the wall of the firetube before it starts ashing.
I can see small blue flames thru the sight hole . I thought that would burn off gas . Blower just kicked on and the asher ran a few minutes after that completed it's cycle and blower is still running . See if she pops ! I will try dropping the grate temp 5°see if that helps. It gets pretty frustrating after awhile . Funny no one from alternate heating seams no anything about puff backs . To bring the boiler backup to temp blower runs longer because of air coming in thru the flap and over the fire. She just ran for 20 minutes to bring boiler back to 175°. Blower runs when it goes down to 160°. Outside temp is 25°.no puff back .
- Freddy
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Hotblast gave you the most important key to this puzzle. You must change the wiring a bit so the asher can not run unless the fan is also running. I have a friend that has your exact boiler and that was the final thing for him. Since the re-wire he has had no puffbacks. One other thing he did which seemed to help some, is not FILL the hopper. He keeps enough in it for a day and a half or so, but always less than half full. We don't know if that really helped or not, but it seemed to so he continues that practice.
- hotblast1357
- Member
- Posts: 5657
- Joined: Mon. Mar. 10, 2014 10:06 pm
- Location: Peasleeville NY
- Stoker Coal Boiler: 1984 Eshland S260 coal gun
- Coal Size/Type: Lehigh anthracite pea
- Other Heating: air source heat pump, oil furnace
Freddy, just for the record, I used to fill my hopper last year by hand, once a week usually, now with the auger it only keeps it about 1/2 full, I have seen no difference.
- Pa papa
- Member
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- Location: Summerville,PA
- Stoker Coal Boiler: AHS-130
- Coal Size/Type: Pea; anthracite
- Other Heating: oil fired boiler; LP insert
That is the root cause. You correct that by slowing the ashing process either with addition of a couple of solid state timers and/or rewiring to ash only during time the I.D. fan is running.coaledsweat wrote: ↑Sun. Nov. 11, 2018 8:44 pmStop ashing for a bit to raise the fire. Too much fresh coal on top.
I think you just got the wrong person at AHS. They have extensive knowledge of remedial actions for puff backs.
Tell the wife it can be eliminated, hang in there.
For now, you might try lowering the hysteresis down to 1 degree along with lowering the ashing temp.
Last edited by Pa papa on Mon. Nov. 12, 2018 9:19 am, edited 1 time in total.
- lsayre
- Member
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- Location: Ohio
- Stoker Coal Boiler: AHS S130 Coal Gun
- Coal Size/Type: Lehigh Anthracite Pea
- Other Heating: Resistance Boiler (13.5 KW), ComfortMax 75
Ask specifically for a technician named Darren Bricker at AHS. He knows his stuff!!!
But here is what I would do:
-------------------------------------------
Reduce your ashing temperature set-point to 110 degrees.
Reduce your ashing hysteresis set-point to 1 degrees.
Make sure it is wired so it can only ash while the fan is running.
Give it a few days for the changes to take root.
Does your AHS have an LC (Love Controls) brand PID that looks something like this one?
https://www.dwyer-inst.com/Product/Temperature/Pr ... /Series16B
But here is what I would do:
-------------------------------------------
Reduce your ashing temperature set-point to 110 degrees.
Reduce your ashing hysteresis set-point to 1 degrees.
Make sure it is wired so it can only ash while the fan is running.
Give it a few days for the changes to take root.
Does your AHS have an LC (Love Controls) brand PID that looks something like this one?
https://www.dwyer-inst.com/Product/Temperature/Pr ... /Series16B
- McGiever
- Member
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- Location: Junction of PA-OH-WV
- Stoker Coal Boiler: AXEMAN-ANDERSON 130 "1959"
- Hand Fed Coal Boiler: BUCKET A DAY water heater
- Hand Fed Coal Stove: Warm Morning 414A
- Coal Size/Type: PEA,NUT,STOVE /ANTHRACITE
- Other Heating: Ground Source Heat Pump and some Solar
Remember AHS, in the end, had a kit to buy to correct sever cases of flawed limited production by a interim owner.
Long thread on puff back and flawed production caused some ruptured stove pipes many times over and over.
Long thread on puff back and flawed production caused some ruptured stove pipes many times over and over.