A good case for keeping the chimney inside the house when possible.

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stee6043

Minister of Fire
Aug 22, 2008
2,648
West Michigan
I've been running my EKO 40 for just over 2 weeks now. Due to my house layout it was not possible to keep my chimney inside. So I went outside and up the side of the house with a chase (22' of pipe vertical).

With temps at -10 to -15 at night this week and highs of 5-8 degrees during the day I finally reached critical mass yesterday. My boiler sits idle basically all day with no fire in her while I heat from storage. When I get home from work I fire it up. During my starting yesterday it was nearly impossible to get draft from my chimney. With an outside temp of roughly zero when I got home it was just TOO cold. There was zero wind last night as well.

I finally managed to force some hot air up the pipe. I burned with the bypass open until I had flue temps of 650 on the near boiler stove pipe, shut the bypass and prayed. I pretty well filled the basement with smoke during this process. It was tough to keep even a small crack open on either door without smoke coming out. There was never any smoke while the bypass was closed and the fan was running but my flue temps would drop from 650 to 100 in about 5 minutes the first two times I tried it.

At the end of the day I did finally get a good fire going and the EKO ran like a champ all night. But the starting process took me nearly an hour last night and I think I inhaled enough smoke to kill a small farm animal.

So there - if you can keep it inside the experts are right - it's better. If you have to go outside just understand that it can be a bit of a challenge from time to time. If you burn 24/7 it may not ever be an issue...
 
I also had to run the SS chimney outside, it is a PITA to initiate draft but next year I am going to enclose and insulate it that will give better results without loosing home space, I also used single wall at the EKO and I plan to either insulate it or use an insulated pipe there, the pro's are right again!!Dave
 
So if I have a boiler room with 10 ft ceiling that Selkirk runs through that is non insulated I should be considering insulating the space to help draft. I am having some draft issues but didnt think that would effect it..
 
That's where a draft booster fan can help. If you don't have one of those an air compressor can work. Run a small diameter soft copper tube with an on/off valve in it inside the exhaust, (valve outside the chimney), pointing toward the chimney exit of course, and turn the air on some when you are trying to build a fire. The compressed air will start a draft for you and as the chimney warms you can shut off the valve. This will at least eliminate the smoke and save the small animals from being burnt offerings or picking up bad habits.
I used to have a wood add on furnace but had to have an outside chimney. I went with the draft booster. It really helped.
 
Yeah, the draft fan would certainly help. I've never heard of the compressed air trick. Sounds like a fun time. I could have fire, 1000 gallons of pressurized water and compressed air all in the same room. Throw in a few beers and have a party.

So far I've only had this problem once so I don't think I'll make any changes yet. If I start having draft issues at "normal" temps I will certainly be looking into long-term solutions...keeping a bed of coals is my number one priority right now. That alone should help...
 
where would i find out more information on this. Is it something that attaches to the pipe or attaches inside the tarm?>??
 
A draft fan attaches to your flue pipe. I'm sure if you google "draft fan" you'll get loads of hits. It is independant of the boiler...
 
I have a tarm w/o storage and run it 24/7 so I don't build alot of fires from scratch. I seem to recall a section in the tarm manual about getting the fire started that said to get a good kindling fire going with the by pass open and close it about 1/2 way for a while, then close and lock it as usual. You may want to reread that section if its your manual. I have reread that manual several times and discovered stuff I missed the first time through. I think the idea is to let the partially open bypass damper keep your draft going till the refractory gets warmed up enough. Also to get a good kindling fire going I will sometimes run the tarm with the draft fan on, the bypass open, and lower chamber door open which lets a good air supply get to the fire and prevents the smoke from back flowing through the draft fan. Good luck.

jp
 
Cave2k said:
If you don't have one of those an air compressor can work. Run a small diameter soft copper tube with an on/off valve in it inside the exhaust, (valve outside the chimney), pointing toward the chimney exit of course, and turn the air on some when you are trying to build a fire. The compressed air will start a draft for you and as the chimney warms you can shut off the valve.

That's an excellent idea. I have a job right now which is having draft issues due to the efficiency of the boiler (the low flue temps just can't seem to establish draft promptly), and the homeowner has a large compressor a few feet away from the boiler. We may give that a try just for the sake of curiousity.

Joe
 
My stack has excellent draft. (maybe too much) But as part of my installation process, I installed an AD-1. Having had the Wood Gun with negative pressure fire-box with the combustion fan on the output taught me the advantages such as smokeless loading and speedy fire starting. Even if I have only a few small coals in the chamber I can turn on the fan put a couple pieces of kindling or a couple small splits in contact with them and some larger splits on top, open the lower door and let-er-rip while keeping an eye on the stack temp. By the time the stack reaches 400* the load is charred enough to almost immediately start gassing. Shut off the draft inducer, close and latch the lower door, close the by-pass and start the combustion fan. There is a little rumbling as the fire reverses direction and then in no time she's gassing.

The other night when I lit a fire I wanted to check out the speed of gassification so I gave it a few seconds to blow out any unburned gasses so I wouldn't get a face full of fire, opened the door and observed a beautiful blue-white flame overflowing the blocks and still burning as it exited through the tubes.

I usually start the fan when I open the door. I try to be careful not to let any smoke come out because my wife has the nose of a beagle and in a second I hear "I smell smoke." I have a small ozone generating device in the living space which eats up any smoke oder almost instantly. I bought it when I was heating with a pellet stove which always emitted a smoke odor.
 
It is basically a plastic box with an ozone generating black light and a fan in it. My fan started screaming a couple weeks ago so I called the company and they told me they no longer make that unit and tried to sell me some expensive unit. I'll be doing some searches in the next few days/weeks and if I find something to replace it with, I'll let you know.
If you find something in the meantime, I would appreciate it if you let me know.
 
lawandorder said:
can a draft booster be used with a tarm>?? How does it attaach

Not sure about a Tarm, as I have never seen one, but a booster can be made for about any chimney. The one I used for my wood furnace was a Tjernlund (see: Northern tools.com and do a search if you want to see what one looks like) and cannont be used in anything but single walled pipe and I would not use it for my boiler at all. The concept I was refering to with the copper tube extending up into the chimney is more or less a simple venturi nozzle that creates a vacuum when it is in a tube (your chimney) and compressed air is forced out of it. The air from the venturi would be directed so it would exit your chimney top and would create a vacuum or "induced draft" in your firebox.
 
TacoSteelerMan & stee6043, I have a fire/coals going 24-7 with no storage and I have a triple walled chimney that starts at a black T and a short 13" piece of black walled pipe from my boiler. I had a triple walld T last year but the liner was flimsy (old) and took it out. Even so last year I ran into problems putting cold wood into my boiler (outside in an unheated building @ 0 and colder). The cold wood acted as a surface for condensation when the boiler warmed and blown air hit the wood in my EKO40 primary chamber. At first I though it was wet wood causing the problem (would gasify for a short time them actually cool my boiler) but then I used some 3 year old wood that was sheltered after it was split and seasoned. The wood was bone dry when I put it in the boiler and in about 20-30 seconds from placing it in the boiler it was so wet that it would drip or get your gloves wet if you touched it. A real eye opener. Hopefully next year I will have a storage tank, 6-7 cord of seasoned wood and the boiler all in one insulated building. All that to say even with triple walled chimney and with coals there were times I had to fight to get the boiler and fuel up to temp to get sustained gasification. That is a time for stricly dense hard woods.
 
stee6043,
I know you had the draft inducer but you may have removed it. If you still have it, this is how I start a fire and it works well for me: I turn the inducer on, light the paper & kindling & small splits. Close the upper door, bottom door open, now start the controller (positive blower). Let it burn until flue surface temp (not probe) is almost 150 *F (about 10 minutes). Load more wood, pull the bypass closed, turn off inducer & no problems with gasification. I do run the blower(s) at 50% speed.
 
Hydronics said:
stee6043,
I know you had the draft inducer but you may have removed it. If you still have it, this is how I start a fire and it works well for me: I turn the inducer on, light the paper & kindling & small splits. Close the upper door, bottom door open, now start the controller (positive blower). Let it burn until flue surface temp (not probe) is almost 150 *F (about 10 minutes). Load more wood, pull the bypass closed, turn off inducer & no problems with gasification. I do run the blower(s) at 50% speed.

For what it's worth I posted this thread last year when outside temps were staying below zero for several days at a time. I suspect the inducer I have installed this year will dramatically help in this situation if it occurs this year. Starting in general has never really been a problem for me on typical days. 15 degrees below zero will change a lot of peoples system performance if any part of it is outside.

Also - does it take you 10 minutes of burning to get to 150 surface temp on your flue? Is this insulated pipe you're measuring from? I start my fires similar to your method above but never with my pressure fan. Even without the inducer I would typically wait until I have 400 degrees F on my surface temp before closing bypass and turning my fan on. Typically this takes me 10-15 minutes total. My flue surface temps are 150 degrees within a few minutes or so of starting a fire just about every time, especially with my inducer installed. 150F is usually too cool for me to try to gassify.
 
stee6043 said:
Hydronics said:
stee6043,
I know you had the draft inducer but you may have removed it. If you still have it, this is how I start a fire and it works well for me: I turn the inducer on, light the paper & kindling & small splits. Close the upper door, bottom door open, now start the controller (positive blower). Let it burn until flue surface temp (not probe) is almost 150 *F (about 10 minutes). Load more wood, pull the bypass closed, turn off inducer & no problems with gasification. I do run the blower(s) at 50% speed.

For what it's worth I posted this thread last year when outside temps were staying below zero for several days at a time. I suspect the inducer I have installed this year will dramatically help in this situation if it occurs this year. Starting in general has never really been a problem for me on typical days. 15 degrees below zero will change a lot of peoples system performance if any part of it is outside.

Also - does it take you 10 minutes of burning to get to 150 surface temp on your flue? Is this insulated pipe you're measuring from? I start my fires similar to your method above but never with my pressure fan. Even without the inducer I would typically wait until I have 400 degrees F on my surface temp before closing bypass and turning my fan on. Typically this takes me 10-15 minutes total. My flue surface temps are 150 degrees within a few minutes or so of starting a fire just about every time, especially with my inducer installed. 150F is usually too cool for me to try to gassify.

Sorry, I didn't know that was from last year. It does take a good 10 minutes to get to 150 on the top surface of the inducer, it is a 60 though so about 1.5x the mass to heat up of a 40.
I've never seen flue surface temp above 150 even with clean gasification. I think that is mostly due to operating with one nozzle blocked & I run 50% fan speed & only 1 fan. This works very well for me & was my intent when I bought the boiler. When I get storage installed- hopefully next year I'll try using both nozzles & 2 fans. In theory, using one nozzle should be more efficient than 2 because you can put more of the flue gas temp into the water & this seems to be the case in operation. -Same hx area & 1/2 the combustion gas flow.
 
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