Can't Keep Heco 520 Cool

[bholler]

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.

Because they just took the design of a coal stove and added the secondary combustion of a woodstove without changing the things that made it a coal stove. All combination units are compromises that only really do one well. Most are fairly good coal stoves and not very good wood stoves.

 

[begreen]

I wonder if it's referring to the thermostatic damper on the primary there, saying not to use the primary damper while burning wood.

The reference is to varieties of a stove pipe damper.

A stove pipe damper is a logical step to reduce the draft here. Have you called Heco support to get their blessing?

 

[mattie5960]

Because they just took the design of a coal stove and added the secondary combustion of a woodstove without changing the things that made it a coal stove. All combination units are compromises that only really do one well. Most are fairly good coal stoves and not very good wood stoves.

Well, that sucks!

 

[bholler]

Well, that sucks!

You will get it working better for sure as you get things figured out. But there were compromises made to make it dual fuel. And compromises made in heating ability to make it a cook stove. So it won't be as clean burning or efficient as a dedicated wood stove

 

[mattie5960]

Just ordered a damper. I'll work with small fires until it's installed. I'll provide an update with the results, but I'm thinking it'll help quite a bit.

Thank you all for all of you're help and info.

 

[SpaceBus]

I'm having doubts on some measuring equipment if you are having a cooktop that should be glowing (or warped from repeated overfiring) and a flue that is just barely hot and the oven damper is open. I also agree with Ashful that 4-5% moisture content in air dried wood is pretty unusual. Pretty much every single solid fueled cooking stove is primarily a coal stove. The only stoves I can think of that are purpose built for burning wood are the "vertical" style cookstoves with the oven directly above or below the firebox. Pretty much every other stove has an under fire "primary" air inlet which is what a coal fire needs. Under fire air causes wood fires to burn hot and fast, what you are experiencing.


Just one time, try to load the fire, don't use the under fire air, close the secondary as fast as possible, and then engage the oven. I bet your stove top temperature will drop down to 800-ish and after the oven warms up above 300-ish your flue temp will recover back to at least 200f on the surface temp. Are you sure the

I think a flue damper would help your situation, but without engaging the oven damper you will always have raging fires with the very direct flue path.

 

[Ashful]

Just ordered a damper. I'll work with small fires until it's installed. I'll provide an update with the results, but I'm thinking it'll help quite a bit.

Thank you all for all of you're help and info.

I also installed a damper above the stove on my 25-30 foot pipe. Made a huge difference. I keep it nearly fully closed, to keep draft in spec, once chimney is warmed up.

 

[Isaac Carlson]

I agree with the high draft comments.
+1 on the pipe damper.

 

[mattie5960]

I'm having doubts on some measuring equipment if you are having a cooktop that should be glowing (or warped from repeated overfiring) and a flue that is just barely hot and the oven damper is open. I also agree with Ashful that 4-5% moisture content in air dried wood is pretty unusual. Pretty much every single solid fueled cooking stove is primarily a coal stove. The only stoves I can think of that are purpose built for burning wood are the "vertical" style cookstoves with the oven directly above or below the firebox. Pretty much every other stove has an under fire "primary" air inlet which is what a coal fire needs. Under fire air causes wood fires to burn hot and fast, what you are experiencing.


Just one time, try to load the fire, don't use the under fire air, close the secondary as fast as possible, and then engage the oven. I bet your stove top temperature will drop down to 800-ish and after the oven warms up above 300-ish your flue temp will recover back to at least 200f on the surface temp. Are you sure the

I think a flue damper would help your situation, but without engaging the oven damper you will always have raging fires with the very direct flue path.

I haven't been using the under stove air the last few fires. As you said, I'm using only the secondary and closing it off ad fast as possible.

I took the thermometer off the stove pipe and set it next to the one on the stovetop, and they were 15 or 25 degrees off of one another within about 5 mins.

I'll be able to pick up the damper this evening. Gonna let the stove cool off, install the damper, and see how it does. If that doesn't work, I might have to let air circulate to the oven side.

We'll keep breaking the rules of the manual until the stove can be run below 800.

 

[Isaac Carlson]

I don't think you'll get it much below 800. Our cookstove runs 800+ on nearly every burn with stack temps of an almost rock solid 300 on the magnetic thermometer. Pretty clean burning too, with no dedicated secondaries. Ash collects on top of the oven, but I think that's normal. The only thing that comes out of the chimney in the winter is steam. Our house looks like a locomotive on sub zero days/nights. It's real pretty to watch the steam trail off and disappear.

I have seen a faint glow from the top after reloading with oak when I turn the lights off and go to bed. You can't see it with the lights on and it isn't bright with them off, but it is there. Faint red is ~930*F, so it runs 900-1,000* stovetop when it's cold out. It's been running like that for years and should keep going for many many more. It's 1/4" boiler plate, so I'm not worried. The stack temps might rise to 350 when burning that hot, but that's about it.

 

[Ashful]

I'll be able to pick up the damper this evening. Gonna let the stove cool off, install the damper, and see how it does. If that doesn't work, I might have to let air circulate to the oven side.

Keep damper wide open for loading and cold starts. Close to 45-degrees about 10 minutes into burn, or when pipe is showing ~400F. Close full when pipe gets into 500F's, and for remainder of burn.

If you install a manometer, you'll probably find this keeps draft around .05" - .06" WC on a high burn setting, with a chimney of that height. That's ideal for most stoves, based on the few I've actually seen post draft requirements numbers. Draft will climb as you close inlet air, but ignore that, draft is usually only spec'd with stove on high. For your stove, this would likely be with lower (under fire) air closed and upper (air wash) wide open.

As the damper and pipe get gunked up, those bypass holes and the gap around the perimeter of the damper can close up. The effect will be that you'll want to stop before "closed full", based on either manometer measurements or the experience you develop in watching the fire, between now and then.

 

[mattie5960]

I don't think you'll get it much below 800. Our cookstove runs 800+ on nearly every burn with stack temps of an almost rock solid 300 on the magnetic thermometer. Pretty clean burning too, with no dedicated secondaries. Ash collects on top of the oven, but I think that's normal. The only thing that comes out of the chimney in the winter is steam. Our house looks like a locomotive on sub zero days/nights. It's real pretty to watch the steam trail off and disappear.

I have seen a faint glow from the top after reloading with oak when I turn the lights off and go to bed. You can't see it with the lights on and it isn't bright with them off, but it is there. Faint red is ~930*F, so it runs 900-1,000* stovetop when it's cold out. It's been running like that for years and should keep going for many many more. It's 1/4" boiler plate, so I'm not worried. The stack temps might rise to 350 when burning that hot, but that's about it.

This is good info for my nerves. When I take the pipe off tonight I'll lift up the cooktop plates to see if it looks like I've warped anything. Everything on the outside is square, and the same is true for what I can see through the firebox glass.

To be honest, I don't really feel the heat upstairs unless it's running at around 800 or 900, so I'll probably try to keep it around there. It will be nice to be able to control the burn up to that temp, and keep it from hitting the 1000s.

Its been 20s and teens outside here the last couple days, and it'll certainly be colder than that in the winter. I'm gonna have to run it hot to keep the place warm. The house is 3000sqft.

 

[bholler]

This is good info for my nerves. When I take the pipe off tonight I'll lift up the cooktop plates to see if it looks like I've warped anything. Everything on the outside is square, and the same is true for what I can see through the firebox glass.

To be honest, I don't really feel the heat upstairs unless it's running at around 800 or 900, so I'll probably try to keep it around there. It will be nice to be able to control the burn up to that temp, and keep it from hitting the 1000s.

Its been 20s and teens outside here the last couple days, and it'll certainly be colder than that in the winter. I'm gonna have to run it hot to keep the place warm. The house is 3000sqft.

I really doubt you are going to heat 3000 square feet with it. That is asking allot

 

[SpaceBus]

Cookstoves are just poor home heaters to begin with, modern ones are even worse. Even with my modest 1,200 sqft the cookstove can't supply sole heat when it's actually cold out.

 

[Isaac Carlson]

Cookstoves can cook and heat well, if designed properly. Ours will easily make 100,000 btu. It sounds like spacebus undersized his, and the btu's on it look pretty low to me for a heating stove.
Poor insulation, lots of glass, and air leaks can make a house much worse to heat that it would normally be. Ours is all 3 and stays toasty in the winter, meaning a 70-80* average in the house. It was built in 1860 and still has the old log floor. We are making improvements, but it takes time.

$6k for a heco?

 

[mattie5960]

Cookstoves can cook and heat well, if designed properly. Ours will easily make 100,000 btu. It sounds like spacebus undersized his, and the btu's on it look pretty low to me for a heating stove.
Poor insulation, lots of glass, and air leaks can make a house much worse to heat that it would normally be. Ours is all 3 and stays toasty in the winter, meaning a 70-80* average in the house. It was built in 1860 and still has the old log floor. We are making improvements, but it takes time.

$6k for a heco?

It was closer to $5.5 when I put my deposit down in June last year. Originally they thought it would be delivered in October. Then there were steel shortages. Then porcelain shortages. By the time it was done the price went up quite a bit. I ended up paying $6.5k

The heco site says 90k btu / up to 2500sqft. I may not be able to do 70s, but I kept the place around 65 last winter running the oil furnace, anyway. At least this will look better and cost less.

Your house sounds similar to mine. Log cross beams holding up the original half of the house. I bought the place from my grandparents. They lifted the whole structure and set it on 10" blocks, along with the addition. Plenty of improvement for me to do, though. New gets old, eventually.

 

[Isaac Carlson]

Heco says up to 90,000 btu, but they don't give any details. If your 3,000 sq ft is tight and well insulated with no big windows, it might do it. We used to heat with a lopi answer before getting the cook stove. We kept that little lopi glowing all winter and never stopped shoving wood into it. The burn tubes finally melted and the baffle sagged. The fire bricks glowed bright orange/yellow. It is in my shop waiting to get refurbed because the shell is still good. It was the stove we had when the furnace went out and was removed. The cookstove does a much better job without being run hard.

 

[Isaac Carlson]

Our house has a 1500 sq ft footprint. The upstairs is extra. We burn 4-6 cord a year in the cookstove.

 

[mattie5960]

Our house has a 1500 sq ft footprint. The upstairs is extra. We burn 4-6 cord a year in the cookstove.

What stove are you running?

 

[Isaac Carlson]

What stove are you running?

Kitchen queen 480, it's in my signature, right below this text.

It's not a perfect stove, but it works very well. The newer models have mixed reviews, possibly because of the changes they made. I don't know if they make the 480 anymore.

 

[SpaceBus]

My house is well insulated, and my cookstove rated output is the same as my Morso 2b Classic, but the way the two heat is totally different. A good cookstove will dump as much heat as possible into the oven and top rather than the dwelling. Who wants to stand next to a 800f massive stove to cook? My Morso 2b heats the home much better than the Cookstove despite having the same output. Just like a 100k btu free standing stove is totally different than a 100k output cookstove. I'm glad modern cookstoves are poor home heaters, they are supposed to be cooking appliances. The fact of the matter is that *most* homes cannot be heated solely with a cookstove, unless you want to load it constantly with a very soft heat output, ultimately wasting all the oven heat out the flue as it cools off. I use this all to my advantage for shoulder season, and even cold summer morning fires here in Maine. I would not recommend anyone try to heat with only a wood burning cookstove, and the Heco 520 is the one I suggest to anyone who really wants to try.

 

[Ashful]

The heco site says 90k btu / up to 2500sqft. I may not be able to do 70s, but I kept the place around 65 last winter running the oil furnace, anyway. At least this will look better and cost less.

You sound like a good candidate for adopting my current heating method. Like you, I have no hope of ever heating my place 100% with wood, but I can still put one hell of a big dent in the oil bill. Just keep plugging wood into that stove on a schedule that suits you, set your automatic thermostats on your central heating to whatever makes the rest of your family happy, and get back to living life. Make it your own personal mission to keep that stove going, finding the settings that make the burn time match your loading schedule, while keeping the family comfortable.

We can argue how one defines "savings", as I'm keeping my house much warmer for more hours per day, than I ever would if I weren't feeding a stove or two. But if you just consider the BTU's put into the house by wood, then I am on track to save about $7000 in oil this year, thanks to our presently-high prices. Using the same calculation method, my savings most years are over $5k. If I did the reverse calculation, looking at how much oil I used in the brief period before adding wood heat, my savings are just bit less... but we weren't as toasty warm, either.

 

[Hoytman]

Great post! Precisely why I have a duel fuel wood stove. One that I plan to make my own removable stainless steel secondary air set up for. It will be more than good with wood when I do that. It’s already more efficient with nut coal than advertised, so why would I ask for more. $2.50-$3/day is cheap heat...using only half a bag for an entire hourly average for the season.

I’ve burned coal since buying the stove because it’s hands down the cheapest way for me to heat...which saved me north of $2500+ from burning fuel oil. All that while collecting and buying wood the last three years, allowing it to properly season over that time. Getting ahead on the 3-5 years seasoned wood plan because I’m planning for what is ahead...it takes fuel to dig coal.

I knew it would come to this. Fuel prices would rise and eventually coal will rise until it is no longer feasible for me to burn it living this far west. Meanwhile fuel oil prices will also continue to rise and I filled up when it was cheap over 3 years ago. I’m still full.

I love my coal, but I love wood just as much and when fuel oil or electric prices drop I’ll love them too.

One way to think of it...I can stock up on any fuel when it is cheap and have a good supply on hand. I will heat however I can save the most money, whatever that may be at the time.

I will never totally reinvest into the wood cutting business as I did that with my dad when I was young. I might set my son up to do it, but most of my best wood cutting days are behind me for several reasons. Cost for wood here isn’t all that bad yet, but it’s slowly rising as well.

I’ll always have a few years supply of wood on hand as well as a few years worth of coal in hand. That should get my through any price increases of any fuel for awhile.

If I don’t get to build that secondary air tube system quick enough for my coal stove...well I have already planned for that too. I already have a modern tube stove or two in my garage along with a few other pre-epa tanks that do a fine job heating by their own right.. As soon as I can find a BK Princess or King in good shape, used, and for the right price...then I’ll add one or two more stoves to my garage at that time and sell the tube stoves. When times get cold, hard, or both, I can sell them all...make times easier for myself and others and warm the hearts of all parties involved.

All of this helping me save for the cookstove I eventually will buy...to rid me of leaning too hard on propane. Which will free up another home heating stove to sell to someone else. By then, I’ll have added a second chimney in the house and have a heating stove as well as the cook stove going...both barely working hard...ready at a moments notice to crank out the heat, heat my coffee, toast my bread, make my breakfast and dinner, dry my clothes and heat my water. Throw in the summer plate or get the dolly and move it to the breezeway summer kitchen.

 

[mattie5960]

The damper seems to have made quite a large difference.

There are a couple of things to note, first:

• The temperature outside is about 40 degrees right now (up 20-30 from what it's been the last 48 hours or so) which I understand reduces draft
• There's been quite a bit of wind the last couple days. It's now extremely calm, which I also understand reduces draft

The first thing I noticed is that my kindling and starter fire didn't want to take off like it has every other time I've gotten the stove going. I left the pipe damper wide open for the whole starter fire. Once it had mostly burned down to embers, I put two fresh kindling sticks on the embers, two large-ish splits on top of the fresh kindling, and 3 smallish splits on top of those. I left the door slightly ajar to get all the new wood burning, and then closed it off slowly before eventually locking the door hatch. When the stove top temp got to 600 and the fire was getting unruly, I closed the pipe draft all at once. From there I began slowly shutting down the secondary air.

After putting the fire out 3 times now, the most I can shut down the secondary is to about 45%. The flames are just billowing at the top of the firebox. They are still rolling around the baffle and lapping at the cook plate (stove top), but not as aggressively as before. The stove top temp (measured right above the firebox, where the flames are lapping) has been a little over 900 for maybe 45 minutes or so, and it seems to have stabilized there. The logs are breaking down, but still putting off gas. The build up to this temperature took at least twice as long. The stove pipe temperature above the damper is at 280, or so. No smoke coming out of the chimney.

Overall, this seems to be a vast, vast improvement. I'm not sure I could make the stove any cooler without using less wood (or doing a better job at keeping it from getting to 900. Maybe close the pipe damper before a 600 degree stove top). I would like to try "loading her up" and seeing if I can get the same heat but with more fuel for a longer burn time, but I'd like repeat this experience a few more times before I risk melting the stove again (ha).

I'll follow this post with pictures of what the inside of the stove and the stovepipe looked like.

 

[mattie5960]

To my eye, everything looked pretty clean, but I don't know how much damage I could've done in the handful of fires I'd built unless I let every one of them smoulder from start to finish. There's a bit of creosote on the bottom of the cook plates, but I'm sure that's from the decision I made with the fire earlier today to let it burn a little inefficiently at 900 rather than seeing what 1100 degrees was like again. Nothing looks warped. The stove weights about 850 pounds. There's so much metal, I think it's able to absorb the heat and throw it pretty effectively (apprently).

Stove pipe:


Chimney Liner:


Cook plates (stove top):


Inside top of stove, top of baffles:


Exhaust port:


Inside firebox: