Smoke venting from coal hopper of Keystoker stove

Smoke venting from coal hopper of Keystoker stove

PostBy: petebrew On: Tue Oct 30, 2007 9:21 pm

Moved in a few months ago to a house with a Keystoker stove. I have had a go with it this week and it works well except I'm getting a small but steady quantity of smoke drifting out of the coal hopper. It's not really bad but the room feels like an Irish bar (prior to smoking ban!).

I've had it professionally serviced but not entirely convinced the guy knew what he was doing.

Is this standard for a coal stoker? If not, can you suggest what might be wrong. I'm asthmatic and I'm not sure I can take this all winter!!!

Many thanks


PostBy: coal berner On: Tue Oct 30, 2007 9:37 pm

Welcome to the forum Petebrew Take the Hopper off and Replace the
gasket that goes between the Stove and Hopper If that is wear the smoke
is coming out of Or is it comeing out of the top of the Hopper around the
lid let us know
coal berner
Stoker Coal Boiler: 1986 Electric Furnace Man 520 DF
Stove/Furnace Make: Electric Furnace Man
Stove/Furnace Model: DF520

PostBy: jpen1 On: Tue Oct 30, 2007 10:26 pm

Sonds like a draft problem and or a gasket problem. Is the stove a direct/power vent or hooked to a chimney. If a power/direct vent is the venter on/working? Do you have a CO detector? If you don't have one you need one. A stoker shouldn't smoke at all into the room unless it is the first burn after being repainted or the inside was oiled to prevent corrosion over the summer. Check your vent pipe and chimney if you have one and make sure the flue is clean. Also check to see if your barometric damper is set properly if you have one, a keystoker direct vent won't have a baro damper on it. Also if it has a keystoker direct vent the joint of the flue pipe need to be sealed as the flue gasses are under positive pressure. Check that stuff first the only other thing that comes to mind is the strongback gasket under the grate may be worn out or installed incorrectly but this really sounds like a draft issue
Stove/Furnace Make: Leisure Line
Stove/Furnace Model: 110 Boiler

Visit Lehigh Anthracite

PostBy: Matthaus On: Tue Oct 30, 2007 10:51 pm

One thing to do immediately! If you do not have a couple CO detectors in the area around the stove shut it off and go get some! :shock:

If you are seeing smoke there is definitely some kind of problem. As Jpen said it probably is draft related. I have seen many Keystokers with burn marks where the fire has tried to run into the hopper due to improper draft.
You should do an inspection around the area where the hopper meets the stoker unit, if there is any signs of overheating, shut down the stove and do a thorough inspection.

But while you are figuring out exactly what is going on you need a couple CO detectors to keep you and yours from harm. PLEASE! :)
Stoker Coal Boiler: Leisure Line WL110 Dual Fuel, natural gas
Hot Air Coal Stoker Stove: Leisure Line Lil' Heater (rental house)
Coal Size/Type: Rice and Buckwheat Anthracite

PostBy: Richard S. On: Tue Oct 30, 2007 11:23 pm

Matthaus wrote:One thing to do immediately! If you do not have a couple CO detectors in the area around the stove shut it off and go get some! :shock:

This should be repeated so i will, it is utmost imporatnce. And no that is not normal.
Richard S.
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

PostBy: petebrew On: Wed Oct 31, 2007 8:31 am

Many thanks all. Appreciate you all worrying about us but no need - I bought a CO detector before I fired her up. :)

I'll take her to pieces at the weekend and check out all your suggestions. I'll post back when I work out what it was.


PostBy: WNY On: Wed Oct 31, 2007 8:44 am

We have had our Keystoker 90 for 3 years now and never experienced that, ours was a direct vent and now hooked to the chimney with good draft without the direct vent blower.

Definately sounds like a drafting issue, check your pipe, Baro Damper if you have one, get a draft gauge and check it.

maybe your combustion blower is pressurizing the stove too much and the draft can't pull it out fast enough. Our Combustion blower has a cover over the inlet that is half covered up.
Hot Air Coal Stoker Stove: Keystoker 90K, Leisure Line Hyfire I
Coal Size/Type: Rice
Stove/Furnace Make: Keystoker, LL & CoalTrol
Stove/Furnace Model: 90K, Hyfire I, VF3000 Soon

PostBy: europachris On: Wed Oct 31, 2007 10:52 am

My Keystoker direct vent showed a lot of evidence of draft issues around the hopper area. But, it was not well maintained by the previous owner and was clogged solid with ash all over.

Since totally rebuilding it and knocking about 10# of fly ash from up in the heat exchanger area, it burns perfectly with absolutely no smoke from the hopper and no evidence of trying to burn back at all. I run about .02 draft with the direct vent unit (on a speed control turned down just a bit) and the combustion blower is 1/2 covered on the inlet.

Now I just need to wait for some good cold weather so I can let it run.

Stove/Furnace Make: EFM 350/Iron Fireman
Stove/Furnace Model: Custom bituminous burner


PostBy: byrdy11 On: Thu Nov 01, 2007 3:43 pm

This happened to me last year and I thought it was a leaking seam (wasnt). My power vent was clogged with ash and when I took it apart, vacuumed it and oiled it (had to scrape hte ash out with a screwdriver) then it was fine. I had emptied the chimney pipe, but, knowing really nothing about the stove, I fired it up without cleaning up the ash from the previous season and I saw the same thing.
Hot Air Coal Stoker Furnace: keystoker 90
Coal Size/Type: rice


PostBy: petebrew On: Sun Nov 04, 2007 4:53 pm

Thanks for all the tips. I also managed to find another company an hour away who were kind enough to talk through my problems.

The main issue seems to have been the fact that the 'professional' that serviced my stove didn't cement the grate into place which he removed to clean. Air was therefore leaking out all the way up the grate so that the fire was burning way too high up the slope. If I wasn't so British i'd sue the guy! ;) I cemented the grate in and let it dry overnight. I lit it again this afternoon and the smoke is a lot better but there is still some coming up through the coal in the hopper and also a little coming through the stoker mechanism.

Several of you recommended partially covering the air intake on the combustion blower. The duct leading to the fan is sealed and I can't see any way of limiting the air getting in :( - any suggestions?

I really could do with a professional who knows what they are doing - especially after the last guy! Is it against forum policy to ask for recommendations around the Ithaca, NY area?


More CO

PostBy: petebrew On: Sun Nov 04, 2007 9:08 pm

Grr... I thought I'd got it working ok but after it had run for 4 hours with no visible smoke coming out, the CO detector went off.

I've attached a photo of the state of the grate when the alarm went off. Shouldn't the burning bit be further down the slope?
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Re: Smoke venting from coal hopper of Keystoker stove

PostBy: jpen1 On: Sun Nov 04, 2007 9:14 pm

Shut it down and open up some windows immediately. CO is nothing to play around with.
Stove/Furnace Make: Leisure Line
Stove/Furnace Model: 110 Boiler

Re: Smoke venting from coal hopper of Keystoker stove

PostBy: jpen1 On: Sun Nov 04, 2007 9:25 pm

Is the unit a direct/power vent or vented into a chimney? If you are getting CO into the house you have either a draft issue or a gasket issue. I'm still betting it is a draft issue since you sealed the grate and fumes out thehopper are almost always indicative of draft issues. Is there moisture on the hopper lid?
Stove/Furnace Make: Leisure Line
Stove/Furnace Model: 110 Boiler

Re: Smoke venting from coal hopper of Keystoker stove

PostBy: europachris On: Mon Nov 05, 2007 9:45 am

Take a look at my thread here:

I notice you have an older version of Keystoker like mine with the cast iron grate on the hot air output. I'm trying to do a little research on how Keystoker has changed the design of the stove internals over the years. The way mine is setup the hot gasses pass through two tubes at the top of the firebox and into a heat exchanger area, centered right behind the hot air grille. These hot gasses then pass down the sides of the stove body and down to the ashpan area. Very effective at heat output, but also very effective at filling up with fly ash. This heat exchanger area is large, flat, and difficult to clean.

Two things on my stove that I noticed when I bought it - 1) It had draft issues BAD! Lots of evidence of heat and fumes around the stoker/hopper area. 2) It was plugged solid. Under the grate was completely full of ash and coal fines, and during the moving of the stove, it was placed on it's side several times, which knocked POUNDS of ash from the upper heat exchanger area. I can't imagine how that stove burned very well.

Since rebuilding it, cleaning it out, re-sealing the grate from the rear joint all the way up to the first row of holes with fire cement, and adjusting the draft on the power vent, she's burning flawlessly.


You need at least -.02 draft to burn properly, and -0.04 is optimum if yours is not a direct vent.
Stove/Furnace Make: EFM 350/Iron Fireman
Stove/Furnace Model: Custom bituminous burner

Visit Lehigh Anthracite