No real secondary burns

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Jesepi

New Member
Nov 19, 2021
30
NW Pennsylvania
Fellas and gals, I'm not really seeing secondary burns like I think I should. I wait till my stove comes up to temp {350 - 500f}
and then I shut the draft down I close the " slide baffle " and I see the flames drop down but no secondary burn. I'm running the WSL-1800 medium stove from
Pleasant Hearth. Other than that I like the stove. I'm burning seasoned Cherry wood. The stove manual doesn't even mention secondary burn.
I have 3 or 4 stainless tubes on top with holes. Every once in a while I will see some flame coming from those tubes but just barely.
Any ideas ?
 

stoveliker

Minister of Fire
Nov 17, 2019
4,353
Long Island NY
And do you have enough draft? How tall is your chimney?

Have you checked for a blockage in the secondary air pathway?
 

Jesepi

New Member
Nov 19, 2021
30
NW Pennsylvania
And do you have enough draft? How tall is your chimney?

Have you checked for a blockage in the secondary air pathway?
The chimney is 21 feet out side thru the wall. It is triple wall insulated and the draft seems to be great. I believe the secondary pathways are in the rear. Whats the best way to check for any blockage ?
 

kennyp2339

Minister of Fire
Feb 16, 2014
6,541
07462
More then likely the pathway isnt blocked, the intake is next to the primary intake on the bottom of the stove, figure secondary reburn occurs when the internal firebox reaches over 1100deg f, if your burning and go outside you should have some steam or just heat vapors after loading the stove and dialing down the primary air and waiting a good 15min afterwards. A good thing to do is check your cap, make sure there isnt any build up, you can also open the loading door when theres some fire going, if you get a waft of smoke that hasnt happened before then its time to do a cleaning on the chimney.
Moisture is measured on a room temp split that is re-split and on the fresh face.
 

Jesepi

New Member
Nov 19, 2021
30
NW Pennsylvania
More then likely the pathway isnt blocked, the intake is next to the primary intake on the bottom of the stove, figure secondary reburn occurs when the internal firebox reaches over 1100deg f, if your burning and go outside you should have some steam or just heat vapors after loading the stove and dialing down the primary air and waiting a good 15min afterwards. A good thing to do is check your cap, make sure there isnt any build up, you can also open the loading door when theres some fire going, if you get a waft of smoke that hasnt happened before then its time to do a cleaning on the chimney.
Moisture is measured on a room temp split that is re-split and on the fresh face.
I am a new wood burner so when you say firebox should be up to 1100 deg what would be the temp showing on my Rutland magnetic thermometer on the stove top ? This is a new install so I check the cap and chimney every few days to see how it is operating as far as creosote build up. The cap is clean and I really never have seen any smoke from the chimney.
 

kennyp2339

Minister of Fire
Feb 16, 2014
6,541
07462
I am a new wood burner so when you say firebox should be up to 1100 deg what would be the temp showing on my Rutland magnetic thermometer on the stove top ? This is a new install so I check the cap and chimney every few days to see how it is operating as far as creosote build up. The cap is clean and I really never have seen any smoke from the chimney.
You want to shoot for an operating stove top temp of 450 - 700 deg f, no smoke is a good indication that your burning cleaner, if you bump up the stove top temps then you'll see more active fire and secondary's. Try adjusting your air control in quarter increments, allow 15 - 20min per adjustment so the fire can settle in, also make sure you have more then 3 splits in there to get a true handle of whats going on. You should be able to find the stoves sweet spot and remember that setting, of course draft changes with the weather so on warmer days you may need more air, on colder days you may need less air to achieve the same results.
 
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bigealta

Minister of Fire
May 22, 2010
713
Utah, NJ
Are you filling the firebox full? If there is not enough wood in it, it will most likely just burn with maybe some secondary, but mostly primary flames.
 

Jesepi

New Member
Nov 19, 2021
30
NW Pennsylvania
You want to shoot for an operating stove top temp of 450 - 700 deg f, no smoke is a good indication that your burning cleaner, if you bump up the stove top temps then you'll see more active fire and secondary's. Try adjusting your air control in quarter increments, allow 15 - 20min per adjustment so the fire can settle in, also make sure you have more then 3 splits in there to get a true handle of whats going on. You should be able to find the stoves sweet spot and remember that setting, of course draft changes with the weather so on warmer days you may need more air, on colder days you may need less air to achieve the same results.
Okay I will try that today. My rutland thermometer shows 600f as overfire. Im always nervous to get to those temps. Ill give it a whirl and see what happens. Thanks.
 

stoveliker

Minister of Fire
Nov 17, 2019
4,353
Long Island NY
The chimney is 21 feet out side thru the wall. It is triple wall insulated and the draft seems to be great. I believe the secondary pathways are in the rear. Whats the best way to check for any blockage ?

If not easily done visibly, I'd see if you can (on a cold stove, and with a person to help) put a vacuum cleaner on the secondary air intake, and then feel whether air gets sucked into the tubes in the firebox.
Or, if you have a decent constant source of air blowing (e.g. the backside of a shop vac), you can blow into the secondary air intake.

But the other advice may be better.
 

kennyp2339

Minister of Fire
Feb 16, 2014
6,541
07462
My rutland thermometer shows 600f as overfire.
Chances are that thermometer is not a stove top, but a chimney pipe thermometer, they are calibrated differently because chimney pipe is much thinner, buy a toy, infrared thermometer, make sure you get the one that can read to 1,000deg f
 
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saberbass

Member
Feb 20, 2020
34
Brandon, MB, Canada
My secondaries don't take off till my stove top is 700 degrees, and the flue is 500-600. I do a cold start every day and the first fire is a log down with about 3 splits, diced up to 20 small thin ones. that brings the stove a flue up to temp. Then i put 4 good size splits in and after they char all over and start burning good i turn the air down and the secondaries take off. maybe your stove is not hot enough ?
 

bigealta

Minister of Fire
May 22, 2010
713
Utah, NJ
yeah thats what it usually looks like. I may get a few flames coming out 5 holes on one side of the burn tubes.
post a couple pics of your firewood load and when burning.
 

snobuilder

Feeling the Heat
Dec 16, 2021
431
WI
Are you filling the firebox full? If there is not enough wood in it, it will most likely just burn with maybe some secondary, but mostly primary flames.
So the fire box has to be constantly tended to keep it full to achieve a secondary burn?
 

stoveliker

Minister of Fire
Nov 17, 2019
4,353
Long Island NY
No. Only upon reloading.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,466
central pa
Okay I will try that today. My rutland thermometer shows 600f as overfire. Im always nervous to get to those temps. Ill give it a whirl and see what happens. Thanks.
That is a stove pipe thermometer not a stove top thermometer. The value ranges are not accurate for your application
 

bigealta

Minister of Fire
May 22, 2010
713
Utah, NJ
So the fire box has to be constantly tended to keep it full to achieve a secondary burn?
Nope, but if you only start with a few small splits, that's probably not gonna cut it.
 

bigealta

Minister of Fire
May 22, 2010
713
Utah, NJ
So the fire box has to be constantly tended to keep it full to achieve a secondary burn?
Nice Try, Is that what i said? Or implied? Nope.
 
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snobuilder

Feeling the Heat
Dec 16, 2021
431
WI
Nope, but if you only start with a few small splits, that's probably not gonna cut it.
I don't see anything about a "few small splits" being his only fill...LOL.... whos" implying" or "making up whatever you want" now?
Sounds like YOU.
You implied he wasn't using enough wood which I thought was the complete opposite idea of these new stoves?? No?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,466
central pa
I don't see anything about a "few small splits" being his only fill...LOL.... whos" implying" or "making up whatever you want" now?
Sounds like YOU.
You implied he wasn't using enough wood which I thought was the complete opposite idea of these new stoves?? No?
You need enough wood in the firebox to get it up to operating temp. I the temps aren't up secondary combustion won't occur.
 

bigealta

Minister of Fire
May 22, 2010
713
Utah, NJ
I don't see anything about a "few small splits" being his only fill...LOL.... whos" implying" or "making up whatever you want" now?
Sounds like YOU.

Nope wrong again, i originally Asked if op was filling firebox. Then added that if not (using a small load three small splits for example) that Could be his problem.

You implied he wasn't using enough wood which I thought was the complete opposite idea of these new stoves?? No?

And yes if you only use a small amount of wood (fuel) it will not burn great and produce much heat, same as a non epa.

"You implied he wasn't using enough wood which I thought was the complete opposite idea of these new stoves?? No?

Yup could be not enough to fuel. And Nope you thought wrong if you think they are supposed to run with little fuel.

How long and hot does your stove run on little fuel?
 

wagne223

Member
Jul 10, 2019
57
North Florida
I tend to look at this way.....
Getting to secondary combustion is a balance between heating and maintaining flue temp and keeping heat in the firebox.
To increase fire box temp as fast as possible, you have to slowly close the primary air.
Most recommend closing in 1/4 increments. Close, monitor flue temp. Repeat. Until you find the sweet spot. That is good secondary combustion, flue temp normal and stove temp at your desired output.
Some setups can close primary all the way. Some can't.
Mine cruises best at 1/8 open primary.
Most of the fun has been figuring out how to run my stove!