Can't Keep Heco 520 Cool

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What are your pipe temps when the stove is that hot?
I'm lucky if the pipe gets over 300, no kidding. And if it does, it doesnt stay there long. As soon as the flame is off the logs it drops to 250ish or lower. It makes it that much more important that I make sure the wood is burning efficiently, cuz a lot of the time the pipe is barely over 250, if not lower. And, of course, keeping a flame on the log spikes the stove top temp.
 
Engage your oven and that will bring down stove top temperatures immensely. I always engage the oven when I'm burning a full load of fuel. If you want to cook and not heat the oven only burn small, fast, hot fires and leave the oven damper open.
 
I'm lucky if the pipe gets over 300, no kidding. And if it does, it doesnt stay there long. As soon as the flame is off the logs it drops to 250ish or lower. It makes it that much more important that I make sure the wood is burning efficiently, cuz a lot of the time the pipe is barely over 250, if not lower. And, of course, keeping a flame on the log spikes the stove top temp.
That is single wall pipe correct?
 
Engage your oven and that will bring down stove top temperatures immensely. I always engage the oven when I'm burning a full load of fuel. If you want to cook and not heat the oven only burn small, fast, hot fires and leave the oven damper open.
That will also drop pipe temps further which are already on the cool side
 
Engage your oven and that will bring down stove top temperatures immensely. I always engage the oven when I'm burning a full load of fuel. If you want to cook and not heat the oven only burn small, fast, hot fires and leave the oven damper open.
From the manual:

"Do not set the cookstove to bake mode if you are not baking. This will decrease the lifetime of your cookstove's oven box and require more frequent creosote cleanout."

Not that it wasn't a good idea, but the manual recommends against it.
 
I still suspect you have very strong draft if all this is happening with the oven engaged. Is there a manual-approved way to reduce draft?
I just reread the paper manual and I actually can't find the part where it says I shouldn't install a pipe damper that somebody else quoted. Under the troubleshooting section it actually lists installing a stovepipe damper for when the fire is difficult to control...

Will adding a damper increase my pipe temps?
 
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I just reread the paper manual and I actually can't find the part where it says I shouldn't install a pipe damper that somebody else quoted. Under the troubleshooting section it actually lists installing a stovepipe damper for when the fire is difficult to control...

Will adding a damper increase my pipe temps?
Edit: I misread your post, a flue damper should increase flue temps. I always use my oven damper as a fire control tool, but my oven is all stainless and my stove is made of an alloy. I am honestly surprised your manual says not to use the oven bypass for anything other than baking. My stove manual says to engage the oven unless you want a short hot fire. Do what you feel comfortable with, but I would be engaging the oven when my flue hits 200f+ on surface temp. That correlates with 150c on my oven thermometer with the bypass open, so I don't monitor flue temps. I know everyone says to keep the internal flue temp over 250f to prevent accumulation of creosote, but after two years of running a cookstove with an exterior chimney 90% of my buildup occurs in the stove and is pretty minimal. My exterior chimney vibrates in the wind and any accumulation falls into the cleanout tee, which is always minimal.
 
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Lots of factors to be consider when trying to answer that question. A good question, but one with not so straight forward am answer.

Spacebus, your first sentence I could agree with if that comma was replaced by a period. That totally changed the meaning of your sentence. That and considering other factors.

I’m as surprised as you are about the manual saying not to use the oven bypass.

That said, I wouldn’t be afraid of his low pipe temps creating creosote in a cookstove with a 500-800 degree stove top...let alone one with an 1100 degree stove top. Other opinions may vary.

I also happen to think you’ll get better more specific answers by calling and talking to Heco. Maybe I am wrong, but the name Dave comes to mind. I think you’ll get your best answers there.
 
Lots of factors to be consider when trying to answer that question. A good question, but one with not so straight forward am answer.

Spacebus, your first sentence I could agree with if that comma was replaced by a period. That totally changed the meaning of your sentence. That and considering other factors.

I’m as surprised as you are about the manual saying not to use the oven bypass.

That said, I wouldn’t be afraid of his low pipe temps creating creosote in a cookstove with a 500-800 degree stove top...let alone one with an 1100 degree stove top. Other opinions may vary.

I also happen to think you’ll get better more specific answers by calling and talking to Heco. Maybe I am wrong, but the name Dave comes to mind. I think you’ll get your best answers there.
Thanks, I edited my post, it was a misunderstanding.
 
Lots of factors to be consider when trying to answer that question. A good question, but one with not so straight forward am answer.

Spacebus, your first sentence I could agree with if that comma was replaced by a period. That totally changed the meaning of your sentence. That and considering other factors.

I’m as surprised as you are about the manual saying not to use the oven bypass.

That said, I wouldn’t be afraid of his low pipe temps creating creosote in a cookstove with a 500-800 degree stove top...let alone one with an 1100 degree stove top. Other opinions may vary.

I also happen to think you’ll get better more specific answers by calling and talking to Heco. Maybe I am wrong, but the name Dave comes to mind. I think you’ll get your best answers there.
If the flue temps are to low it will produce creosote no matter how hot the stove is.
 
Some creosote with any wood stove, cookstove or not, is relative and just to be expected. The proper question isn’t if it will produce creosote, but how much. Also, how often to inspect the system, and how often to clean the system.
 
Some creosote with any wood stove, cookstove or not, is relative and just to be expected. The proper question isn’t if it will produce creosote, but how much. Also, how often to inspect the system, and how often to clean the system.
If flue temps go much lower than that it will make lots of creosote. With a tall chimney it may be already higher up in the chimney.

And no not all stoves deposit creosote in the chimney at all
 
I just reread the paper manual and I actually can't find the part where it says I shouldn't install a pipe damper that somebody else quoted. Under the troubleshooting section it actually lists installing a stovepipe damper for when the fire is difficult to control...

Will adding a damper increase my pipe temps?
Page 4, item #17 under the Safety Instructions.
Screen Shot 2022-03-29 at 6.58.47 PM.png
And you are right. On page 17 they contradict themselves. Perhaps that is a recommendation for coal burning?
 
If the flue temps are to low it will produce creosote no matter how hot the stove is.
A fraction of a percent of the weight of the wood ends up as creosote in the exhaust stream in a clean burning fire. I find it builds up in the stove long before it builds up in the flue. While fundamentally I agree with you, in real life applications it's a meaningless distinction. I would be putting in a pipe damper and using the oven damper to control this Heco if it were in my house, but I understand all of the advice that is concerned with staying in the bounds of the manual, warranty, and applicable safety laws.
 
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A fraction of a percent of the weight of the wood ends up as creosote in the exhaust stream in a clean burning fire. I find it builds up in the stove long before it builds up in the flue. While fundamentally I agree with you, in real life applications it's a meaningless distinction. I would be putting in a pipe damper and using the oven damper to control this Heco if it were in my house, but I understand all of the advice that is concerned with staying in the bounds of the manual, warranty, and applicable safety laws.
I agree in general with a cookstove you will get buildup in the stove first. But not if it's running that hot. Something strange is going on here that the stove is that hot but exhaust that cool.
 
Page 4, item #17 under the Safety Instructions.
View attachment 294258
And you are right. On page 17 they contradict themselves. Perhaps that is a recommendation for coal burning?
I wonder if it's referring to the thermostatic damper on the primary there, saying not to use the primary damper while burning wood.

I am starting to think draft is my problem. No matter how diligently I'm trying to back off the secondary air as fast as the fire will let me, I can't find a balance where the stove doesn't continue to heat up. The gasses aren't staying in the firebox long enough for a sufficiently choked secondary to let them ignite, so there's smoke. The only way to give it enough air that it's not smoking is to put so much air in the firebox that the logs keep burning at a faster and faster rate.
 
I wonder if it's referring to the thermostatic damper on the primary there, saying not to use the primary damper while burning wood.

I am starting to think draft is my problem. No matter how diligently I'm trying to back off the secondary air as fast as the fire will let me, I can't find a balance where the stove doesn't continue to heat up. The gasses aren't staying in the firebox long enough for a sufficiently choked secondary to let them ignite, so there's smoke. The only way to give it enough air that it's not smoking is to put so much air in the firebox that the logs keep burning at a faster and faster rate.
Yes as I said early on I am pretty sure you have excessive draft. Combine that with a stove that is really better suited for coal and you end up with extremely high temps.
 
Just a short comment on wood that dry. I had the same sort of raging fire when was burning some VERY dry birch 5 to 9%.
I now mix in other wood at 20 to 25%.
 
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Just to make sure I'm measuring the stovetop temp correctly, I should be measuring on the cook surface directly above the firebox, right?

I ask because at this point the stove has been choked basically all the way down. There's nothing but a rolling cloud of fire at the top of the box, and the temp climbed up to about 1000. Stove pipe temp is at a little over 200.

Fire is hot. And the thermometer is placed such that there's nothing between the flame and itself except for the steel cook plate. The flames are rolling around the baffle and lapping directly against the bottom of the thermometer, basically.

As long as the secondary burns at the top of the firebox, I just can't imagine the thermometer isn't going to read very hot.
 
Just to make sure I'm measuring the stovetop temp correctly, I should be measuring on the cook surface directly above the firebox, right?

I ask because at this point the stove has been choked basically all the way down. There's nothing but a rolling cloud of fire at the top of the box, and the temp climbed up to about 1000. Stove pipe temp is at a little over 200.

Fire is hot. And the thermometer is placed such that there's nothing between the flame and itself except for the steel cook plate. The flames are rolling around the baffle and lapping directly against the bottom of the thermometer, basically.

As long as the secondary burns at the top of the firebox, I just can't imagine the thermometer isn't going to read very hot.
It does have an insulated baffle in place doesn't it?
 
Aside from wondering why you chose a coal-fired cookstove for heating a house with wood, I'm wondering how on earth you achieved 4% - 5% moisture content on wood in PA. That's way below our equilibrium MC% for wood stored under cover. Was this wood kept in a kiln until hours/days before use? If left in a shed, barn, or any space not immediately adjacent to a heat source, that wood will rise to somewhere in the low-teens MC%, sitting in PA at this time of year.
 
It does have an insulated baffle in place doesn't it?
Yes, it does. But as I said, the flames tend to roll around the baffle and lap up against the steel top when there's a good flame.

@Ashful, this is a result of me not knowing anything and figuring it out as I go. I wasn't stabbing the prongs deep enough into my wood to get a real reading. Fresh splits this morning, shoving the prongs into the wood, it was reading 16% ish.

I'm not sure why people are saying this is coal stove that can kinda do wood on the side. I've not seen any material that's suggested it shouldn't be able to burn wood well, except for the comments here.
 
Yes, it does. But as I said, the flames tend to roll around the baffle and lap up against the steel top when there's a good flame.
That is because you have to much draft. The flames shouldn't wrap around all that much