Creasote in cooking chamber of ewb-100 econoburn.

[Northern Heat]

I recently installed a Econoburn ewb-100 and have been really pleased with it to date .The only thing with the local wood situation is I burn a lot of pine and the top chamber of the unit does get pretty gooey with that black stuff.Especially around the lower part of the door opening.I seem to be getting really good combustion in the lower chamber and I realize that most of the creasote melts down the boiler walls into the burn zone eventually.It really builds up quick, and I was wondering if it is PURE creasote or a sugary tar from the cooking process?? More from a health standpoint than anything . My bottom chamber is dry as a whistle. Was thinking of switching to birch but perhaps I would have the same problem if it is a cooking buy product of all woods?

Interested in what u think.
Thanks

 

[Gooserider]

Creosote is a common byproduct of all wood combustion, but pine more so than other varieties, unless it is really well dried. There isn't a significant difference between the KIND of creosote that you get from pine versus other woods however. In terms of health effects, the stuff isn't particularly good for you, but as long as you try not to breathe it, minimize your skin contact, and wash afterwards, it is probably not any worse for you than other common mildly obnoxious substances... Soot and creosote used to do in the old "Mary Poppins" style sweeps pretty early, but they were also often dealing with coal debris, got a lot more exposure, and didn't have anything close to modern hygiene standards... With reasonable care, I wouldn't class it as a major health concern. Unless it gets so thick as to interfere with the boiler operation, I also wouldn't worry about removing it, as it will burn off eventually.

Do you have storage on your system? Generally we find the folks with storage which allows them to run the boiler hard and hot with little or no idling get less creosote buildup. If you don't have storage, try building smaller fires and loading more often, as it is idling that contributes most to the buildup. You will also probably have less buildup concerns as you get into the colder part of the heating season, again because you will spend less time idling.

Switching to birch might reduce the buildup, but I don't know by how much, and considering that birch is a higher BTU/volume wood, you might want to save it for your higher demand times.

Gooserider

 

[Northern Heat]

Thanks for replying .Yes I guess that the health effects are minimal with creasote if you take precautions. I've been burning wood for heat and cooking for over twenty years and I guess that I'm used to it being in the chimney not the stove unless I was burning green wood.But that was when I was green myself.Seeing the amount that is yeilded from one burn in the cooking chamber was new to me. Unfortunatly this year in the far north the summer was a record breaking wet year and my wood did not get as dry as one might hope.Next year a very large wood shed is in order.Even thought of building a wood greenhouse.

The storage had to be put on hold as I was building an addition on the house. The way I have the boiler hooked up right now it is delivering straight to a very thick robust cement pad that makes up the floor of the addition. So I am just throwing the appropriate amount of heat,with 160 degrees to the pad every day depending on the temperature outside.When I get the storage I will add the accuators and zone valves. Needless to say this is not a absolute science and the house temp goes up and down a bit,but not anywhere close to the flucuation of a conventional wood stove.

The size of the load does indeed make a big difference in the amount of creasote build up ,and I have been loading smaller amounts more often ,and it does work well.But it does take that much more effort every day.

Luckily the build up does not get too bad.


Thanks

 

[Gooserider]

A gasifier doesn't really produce any more creosote than any other sort of wood burner, the big difference is that it tends to leave anything that doesn't burn in the top chamber, instead of spreading it out on the walls of your chimney, and into the air that you and your neighbors are wanting to breathe...

Having a slab like you mention does act sort of like storage in some ways, as it has a lot of thermal inertia, where it takes it a long while to warm up, and then another long while to cool back down, but it does help even out the loads. Of course once you do get the storage in, you will find it evens things out even more...

One thing I should ask, just to verify, especially if you are dumping a lot of heat into a slab, is do you have some sort of boiler return protection setup? It is critical with these boilers that your return water stays above about 140°F in order to prevent boiler damaging condensation in the firebox.... This is usually done with some sort of mixing valve or "loading device" that sends a certain amount of the hot water from the boiler outlet back to the boiler intake to mix with the return water and keep it at the right temperature. Do you have such a setup? (If you plumbed per the Econoburn recommended diagrams, or those of most of the other boilermakers, you should be fine...)

Gooserider

 

[wantstoburnwood]

I run an ebw 150 and yes the top chamber does creosote up when I use it. The creosote only builds up so much so the rest burns off when I have a hot fire. I dont have storage so there is a bit of idling. I only burn dry maple and birch so the moisture content doesn't have a big impact on it.

 

[Northern Heat]

The boiler as told by econoburn does not need a mixing valve as it never lets the water get below 154 degrees except at start up when the first loads of water return from the slab.So far it has worked great. Though the proof is in the pudding and only time will tell.
One thing I did today was up the goal temp for the boiler to 165 and that even made a big difference in the creasote build up as it did idle less.Maybe I will bring it up more perhaps 170 would clear up things even more. What temp do you run at? One thing I am worried about is shocking the cement pad but so far no cracking at all,of coarse it never gets above 26 celcius/78 f. The idling is probably the biggest culprit, as my boiler idles 1/3 of the time,or more, once the first few load of heat go to the slab.Like you say storage will make the biggest difference.

Thanks to DON"T PANIC for the creasote info on the harder higher btu woods.We do have a fair amount of birch up here and I cut a lot of it already as I use it for wood turning.Too bad the boiler isn't designed for wood shavings.

I have been reading this boiler forum for about six months and have read a fair amount of what you guys have written.It has all been fairly helpful in the set up of my system. A great resource !!

 

[Gooserider]

The boiler as told by econoburn does not need a mixing valve as it never lets the water get below 154 degrees except at start up when the first loads of water return from the slab.So far it has worked great. Though the proof is in the pudding and only time will tell.
One thing I did today was up the goal temp for the boiler to 165 and that even made a big difference in the creasote build up as it did idle less.Maybe I will bring it up more perhaps 170 would clear up things even more. What temp do you run at? One thing I am worried about is shocking the cement pad but so far no cracking at all,of coarse it never gets above 26 celcius/78 f. The idling is probably the biggest culprit, as my boiler idles 1/3 of the time,or more, once the first few load of heat go to the slab.Like you say storage will make the biggest difference.

Thanks to DON"T PANIC for the creasote info on the harder higher btu woods.We do have a fair amount of birch up here and I cut a lot of it already as I use it for wood turning.Too bad the boiler isn't designed for wood shavings.

I have been reading this boiler forum for about six months and have read a fair amount of what you guys have written.It has all been fairly helpful in the set up of my system. A great resource !!

That 154 is possibly a bit misleading, as it may just be the overall boiler temperature, not the actual temperature of the water entering the boiler right at the return fitting - This is the temp that really matters, as if you have low return temp problems, it's where the damage will occur... Do you actually have a way of monitoring the temp on that return pipe?

Running up the boiler temp will reduce idling, but it does have the potential issue of reducing the margin between the temp where the boiler will go into idle, and when it hits an overtemp event... Often the temp will go up a little after going into idle, so this can sometimes be a problem, but not necessarily... The other thing is it will slightly reduce your efficiency, and increase your wood consumption... The boiler will transfer heat into the water most efficiently when the water is entering the boiler at the lowest possible non-condensing temperature. Raising the boiler target temp cuts into this a bit. Also the higher the boiler temp, the faster the boiler itself will radiate heat to the outside and cool... (This is mostly a concern w/ outbuilding installs, heat radiated from an inside install still warms the house, but it's still a question as to whether you need the added heat in the boiler room)

Everybody's goal temperature varies a bit, depending on the details of their load setup, whether they have storage, and so forth... It is one of those things that you have to experiment with a bit to find your best value in your house...

In terms of the temps going into the slab, it is your call, but I really wouldn't advise pushing excessively hot water into the slab - the experts have a suggested limit, and I figure there is a good reason for it - including looking at the long term slab life...

Lastly, the docs on most of the boilers that I've read seem to say that you CAN burn untreated / painted shavings, sawdust and other processing scraps as long as you keep the amounts reasonable and mix it in with cord wood... Certainly it makes fantastic fire starter, and many people say that it is great in cold weather for getting the boiler up to temp in a hurry... The two main approaches I've seen suggested are to either load part way with cordwood and then add a few scoops of shavings followed by more cordwood, etc. or to pack the shavings tightly into a paper bag and put that in with a bunch of other wood. Either way it puts out a lot of heat when you do this, so I'd save most of the shavings until your peak demand season...

Gooserider

 

[willworkforwood]

Welcome to the forum Northern Heat - another new EB owner is always nice to see. I would be interested to know what temps you have up there (your current temp is probably as cold as it ever gets down here in the deep South :lol: ). You indicate that storage is on the way, so your burning pattern will change once that happens. But you mentioned a "target" temp of 165 - are you referring to the digital number from the controller on the front of the unit? I'm not sure about the 100, but on my 150 this is a fan control set point (the 150 has a 2 speed fan). The "actual" temp that my boiler runs at is from 160 to 190, depending on the upcoming heating load. That 190 max temp is controlled by a high aquastat that's separate from the EB. The gauge on the left side of the boiler shows that temp, which is a close measure of the actual water temp inside of the EB. Also, ditto to all of the comments on creosote in the upper chamber - a thin layer of creosote is normal and expected. However, when you say "gooey", that is probably the effect of either too much idling, and/or wood greater than 20% mc. You can improve this by cleaning extra deposits from the door and bottom door plate. Last year I had wood over 20%, and I used a couple of old drywall knives to knock the extra blobs of creosote off, and also used 2' piece of 3/8" threaded rod to keep the space between the door and door plate free of extra deposits (the rod just barely fits in between and cleans it up in seconds). I didn't try to scrape much - just flaking off the extra high spots worked for me. Lastly, you might want to clean the damper door area (at the back of the boiler) with a small wire brush attached to a long handle. When the fire is down to coals, lightly work the brush from back to front in the damper door area to knock off the larger deposits. This will help stop the door from getting stuck shut from the extra creosote which builds up in that area. I still do all of this maintenance, just less frequently because of better seasoned wood.
Happy burning and good luck with your new boiler!

 

[Northern Heat]

Thanks for the welcome to the forum.

On the ewb 100 the bottom number according to the manual is the temp at an aquastat near the exit of the boiler at top which controls the target temp that I set myself .They suggested starting at 160 and no lower.Although now 165 seems like a more suitable # for my set up,and moisture content for this year.There is another aquastat that they supply that goes into the top of the circulating loop,I also set this to 190.When this aquastat trips it shuts off the blower.The temperature/pressure gauge on the left hand side seems to jive with the digital temp on the front plus or minus a few degrees due to the different positions of the gauges.

Although I have no way of monitoring the temp of the return water at the entry ,I have never seen the temp on either gauge digital or analog, read less than 154 after it has made a heat dump after reaching the goal temp of 160 ,never below 157 with a goal temp 165.Leading me to believe that after the initial warm up the return never see's a 140 degree flow. If it does it must be for an extremly short time. And it never registers this temp on either sensor.

As for sticking door on the top chamber I just rub a bit of high temp silicone on the gasket from time to time and that seems to keep it from sticking.

The weather here right now is fairly above seasonable at -7 C and snowing . So far even with slightly less than optimul fuel my consumption has been about I guess 30% less than last year . Which is in keeping with the difference in efficiency of the two heating units ,the later being a regular generic updraft woodstove.

Tried the wood turning shavings in the boiler layered like you said and wow what a flame right after loading .Thought my boiler was going to rocket off to the moon .Certainly a great way of using it up as I produce enough to fill a small swimming pool every year.

 

[Gooserider]

Thanks for the welcome to the forum.

On the ewb 100 the bottom number according to the manual is the temp at an aquastat near the exit of the boiler at top which controls the target temp that I set myself .They suggested starting at 160 and no lower.Although now 165 seems like a more suitable # for my set up,and moisture content for this year.There is another aquastat that they supply that goes into the top of the circulating loop,I also set this to 190.When this aquastat trips it shuts off the blower.The temperature/pressure gauge on the left hand side seems to jive with the digital temp on the front plus or minus a few degrees due to the different positions of the gauges.

Although I have no way of monitoring the temp of the return water at the entry ,I have never seen the temp on either gauge digital or analog, read less than 154 after it has made a heat dump after reaching the goal temp of 160 ,never below 157 with a goal temp 165.Leading me to believe that after the initial warm up the return never see's a 140 degree flow. If it does it must be for an extremly short time. And it never registers this temp on either sensor.

That sounds like you are probably OK, though I am still of the opinion that it never hurts to be really sure... I figure it is easy enough to do one of the various suggestions for attaching a thermometer of some sort to the return pipe so you can spot check... The method I like is to get one of the low cost digital cooking thermometers they sell for telling when roasts and such are done, and fasten the probe to the return pipe, with some insulation wrapped over it - that will give you the actual return water temp to within a degree or so...

Remember that even if the overall boiler temp is OK, there is a possibility of corrosion right where the return pipe enters the boiler if the return temp is low... Maybe I'm paranoid, but I figure that as much as one of these boilers costs, I don't want to take any chances...

As for sticking door on the top chamber I just rub a bit of high temp silicone on the gasket from time to time and that seems to keep it from sticking.

Good approach, you might also see what some of the EKO guys do, as several of them also seem to have sticking door problems on occasion. (Do a search on EKO Door Gasket)

The weather here right now is fairly above seasonable at -7 C and snowing . So far even with slightly less than optimul fuel my consumption has been about I guess 30% less than last year . Which is in keeping with the difference in efficiency of the two heating units ,the later being a regular generic updraft woodstove.

Sounds good, glad you are up there, and I'm down here - we haven't had any sustained below freezing temps yet, and I like it that way... :coolsmile:

Tried the wood turning shavings in the boiler layered like you said and wow what a flame right after loading .Thought my boiler was going to rocket off to the moon .Certainly a great way of using it up as I produce enough to fill a small swimming pool every year.

Yes, you have to be careful not to overdo on the shavings... The other situation I've heard they are really good is if you have any less than properly dried wood, it is good to mix the shavings in with it... While in theory the drier the wood the better the fuel, in practice the boilers are designed to run best on wood with about 15-18% moisture, and if you get to far below that, you can get over heating. By mixing the chips, which are probably ultra low MC, with wood that has a higher than desirable content, you can end up with an average MC for the load that is pretty good - the damp wood absorbs some of the excess heat from the chips, which speed dries it so that it is perfect for burning by the time the chips are gone... Does take a bit of experimentation to find the best mix for your situation, but can be a good way to both get rid of the chips and stretch your supply of "good" wood...

Gooserider