Creosote Issues... Help??

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
  • Hope everyone has a wonderful and warm Thanksgiving!
  • Super Cedar firestarters 30% discount Use code Hearth2024 Click here
Status
Not open for further replies.

woodburnr

New Member
Oct 10, 2014
2
WI
We are new to burning wood. We've been running our wood boiler for only a couple of days and already have a thick film of sticky creosote on the inside of the fire box and it is now dripping down the outside of the chimney. I know this is due to a cold fire, but I'm unsure how to keep the fire burning hot. The blower only runs when the thermostat tells the system to kick on and, once the house warms up in the morning, it will not run at all the rest of the day. Because of this, the fire is barely smouldering most of the time, even with the dampers wide open. I'm not sure what to do here.

Also, I tried to get a good roaring fire going this morning to try and burn it off, but as the fire got bigger, the creosote began to catch fire, and I smothered the fire for fear of it spreading up the chimney.

Help??
 
It is too early in the year to be running your wood boiler. Additionally, your wood may not be as dry as it should be. Generally speaking a good rule of thumb is "Thanksgiving to the first of March". That is the heating season where it is cold enough that your boiler won't spend too much time smoldering and making creosote. This is not just a maintenance and efficiency issue, it is also a safety issue. I know it's tough to hear the oil or propane boiler come on, but in the shoulder seasons of Fall and Spring, you just need to burn some fossils and leave the wood boiler alone until it is colder outside. See also: thermal storage.
 
  • Like
Reactions: cityboy172
You are echoing my thoughts. Tried telling the other half this to no avail, but maybe with an outside opinion. Though I know our wood is dry as it has been stacked and drying for almost 4 years. Thanks
 
I assume that you have a gasification boiler. Dry wood and thermal storage makes the difference. I run my Tarm all year long. In the summer I might only burn once every 8 or 9 days for domestic hot water, on the coldest winter days I burn twice. With storage I have had no creosote in the flue or tubes and very little creosote in the chimney. The only time we use oil is if we are away for a few days.

I understand your problem. Had a non gasification wood boiler without storage for almost 30 years, used it only during cold weather and still had creosote that plugged tubes and required regular chimney cleaning. Storage and heat exchangers are not cheap but if you have a gasification boiler it is the way to go.
 
Welcome to hearth ! What type of boiler do you have ?

Back in the early 80's we had a boiler like the one in the picture below , it would heat your hose but its real specialty was making creosote .

[Hearth.com] Creosote Issues... Help??
 
Agree with the folks above, can you tell us what kind of wood boiler you have? That will be helpful to help you tweak your system.
 
If your boiler is outside, stand alone and properly located away from your house you may not want to "worry" too much about a chimney fire. I know a handful of outdoor wood burner users that see a good solid chimney fire as an easy way to clean the chimney. Again, assuming it's outside and away from the house.
 
Batch burn very small fires until it gets colder out or add storage. Also sounds like your chimney pipe is put together wrong. The creosote should run down the inside of the chimney pipe not the outside. Maybe just do a small fire in the morning to take the chill off and let the other heat supply maintain it threw the day. Good Luck
 
Sounds like you're running a hot air wood furnace?

And tell your better half that the info you're getting here is correct and lined up with your assumptions. Too early for a fire.
 
Are you using a TV by chance? Wood issue would also be my thought but without a TV you will have creosote issues. Also thermal storage is the way to go if you don't have it already.
 
just my humble opinion, but without storage, the installation will be a creosote monster. It might not be as bad with milder temps, but the same issues will arise. Man, I can't imagine what the heat exchanger tubes look like! YUK!
 
just my humble opinion, but without storage, the installation will be a creosote monster. It might not be as bad with milder temps, but the same issues will arise. Man, I can't imagine what the heat exchanger tubes look like! YUK!

Ohh come on now. Let's not go overboard. Many a boiler (even gassers) have been run plenty clean without storage. Storage is not the end all, be all of burning wood. People who profess that it is are usually misinformed (not saying you are, JT). We don't even know what kind of rig the OP is running yet. Wouldn't we all be shocked if it was an EKO or Tarm? Oiy.
 
Ohh come on now. Let's not go overboard. Many a boiler (even gassers) have been run plenty clean without storage. Storage is not the end all, be all of burning wood. People who profess that it is are usually misinformed (not saying you are, JT). We don't even know what kind of rig the OP is running yet. Wouldn't we all be shocked if it was an EKO or Tarm? Oiy.
Well, for myself , I have an Eko with a puny 350 gallons of storage. If the burns are not properly managed, HEAVY creosote results. My firewood has benn cut/split/stacked/covered since 2011; moisture is 10%...mostly hard and soft maple. For my setup, 500 gallons should have been the minimum, but I simply do not have space for it. I stand by my opinion that properly-sized storage is the key to a happy relatonship with a gasser.
 
I stand by my opinion that properly-sized storage is the key to a happy relatonship with a gasser.
Yes and No. I am a strong advocate of ample storage because it makes burning a gasser easy, convenient, and possibly even long times between firing. Without storage or limited storage, managing the burn/load is very important -- need to load wood volume to match the load quite closely, or increase the load to match the wood volume. Not necessarily easy, nor convenient, and does not permit long burn times between firings.
 
  • Like
Reactions: BoilerMan
You're all correct! Fire management during constant cold temperatures can easily be done. During the shoulder seasons fire management can nearly be impossible in the with the temperature wings we see during those periods. With the light heating load I have, I would be really sour on wood heating with a gasser if I didn't have storage.
 
  • Like
Reactions: JTWALL
Well, for myself , I have an Eko with a puny 350 gallons of storage. If the burns are not properly managed, HEAVY creosote results. My firewood has benn cut/split/stacked/covered since 2011; moisture is 10%...mostly hard and soft maple. For my setup, 500 gallons should have been the minimum, but I simply do not have space for it. I stand by my opinion that properly-sized storage is the key to a happy relatonship with a gasser.

You can certainly accommodate clean burns without storage. The keys are just to ensure the return water temp is always ~140 and that the combustion controls (ie. fans, dampers) are not limited without a call for heat. The second part means that you will have times where your boiler output exceeds your heat load, and you'll need somewhere to put the BTU's (dump zone or other overheat control).
 
Think we need some feedback from the OP on the questions that have been asked of him - mainly, what kind of boiler & system do you have?

It should be possible to operate without storage without getting into the creosote monster category, as long as the wood is dry, but it will require careful & close attention to procedures. Which won't likely jive with a load-in-the-morning-and-again-at-night-when-you-get-home scenario.
 
Well, for myself , I have an Eko with a puny 350 gallons of storage. If the burns are not properly managed, HEAVY creosote results. My firewood has benn cut/split/stacked/covered since 2011; moisture is 10%...mostly hard and soft maple. For my setup, 500 gallons should have been the minimum, but I simply do not have space for it. I stand by my opinion that properly-sized storage is the key to a happy relatonship with a gasser.

Are you talking about creosote in the firebox or in the chimney? We all have "gobs" of creosote in our fireboxes even with thousands of gallons of thermal storage. Par for the course with most of us, for sure us EKO users, even with perfect wood.

I've had a handful of days of heavy idling with my boiler and have never seen anything other than flyash in my stack.
 
Think we need some feedback from the OP on the questions that have been asked of him - mainly, what kind of boiler & system do you have?

It should be possible to operate without storage without getting into the creosote monster category, as long as the wood is dry, but it will require careful & close attention to procedures. Which won't likely jive with a load-in-the-morning-and-again-at-night-when-you-get-home scenario.

Agreed. I think this OP might be a flyby poster.
 
You can certainly accommodate clean burns without storage. The keys are just to ensure the return water temp is always ~140 and that the combustion controls (ie. fans, dampers) are not limited without a call for heat. The second part means that you will have times where your boiler output exceeds your heat load, and you'll need somewhere to put the BTU's (dump zone or other overheat control).
Assessments such as this are true however the conclusion is based on the operator's experience with his particular system. In my case, by the time I have circulating 140 degree water, the upstairs living space is already close to comfort temperature just from the radiation from the boiler, stack and associated near boiler piping. Can't build a fire small enough to heat during shoulder seasons with the higher temperatures. You can't burn just one log or split, even in a gasser. As I've told youngsters when lighting a campfire or a wood burning heater, " that log needs a friend in order to burn". A dump zone vs. storage would be a waste in my opinion plus unless the dump zone is outside it would drive me outdoors. During this time of the year, just bringing my storage to 170 or so is enough to keep my house at 70 with the thermostat switches in the off position.
 
In my case, by the time I have circulating 140 degree water, the upstairs living space is already close to comfort temperature just from the radiation from the boiler, stack and associated near boiler piping. Can't build a fire small enough to heat during shoulder seasons with the higher temperatures.

That's why you need the boiler return water control, designed in a way that allows a small volume of water to be recirculated until it comes up to temp.

A dump zone vs. storage would be a waste in my opinion plus unless the dump zone is outside it would drive me outdoors.

Correct, with storage, it serves as your dump zone. Without storage, there needs to be some way to get rid of excess BTU's.
 
  • Like
Reactions: JTWALL
That's why you need the boiler return water control, designed in a way that allows a small volume of water to be recirculated until it comes up to temp.



Correct, with storage, it serves as your dump zone. Without storage, there needs to be some way to get rid of excess BTU's.
I have my pump launch temperature set at 175 degrees so there is no circulation and only the boiler and is being heated in the early stages of the burn.
 
Status
Not open for further replies.