New Gasifier Owner with a Question

[Blennophobic]

Hi all, I've been reading lots of interesting stuff on this board for the last year or so which convinced me to go with a gasifier system.... see sig for details. Just got the system going over the weekend so I can work out the bugs for next heating season. I do plan to fire once every few days over the summer for DHW pre-heat.

I'm impressed with the operation of the unit so far, but after a little tuning and working out of bugs in my distribution I still have a bit of a problem which seems to be related to lack of draft. I get a lot of smoke out the upper door when I'm loading wood after starting the fire. I actually had it puff back at me today and burn the hair off the back of my hand which was a bit scary. When I go out to the garage to check on it during a burn, there is a smokey haze in the air and quite a strong smell of exhaust or maybe burning paint. I oiled the door gaskets today and adjusted the upper door hinge tighter with no benefit. This has to be fixed because I won't be able to work in the garage next winter like this.

I have about 6-7 ft of 6" stove pipe with a 90 and a 45 elbow. I installed a draft regulator but it never opens. Stove pipe transitions at the ceiling to 6" selkirk for another 14 ft with a 30deg offset elbow kit at the eve.

Questions:
1. Are other people successfully using 6" chimneys on these units?
2. Will the draft pick up substantially in the winter with colder temps?
3. Will I gain much draft by eliminating the offset elbow at the eve?
4. Should I change to 7" chimney?
5. Do these units have a burn-in period where they give off bad burning smells?
6. Should I expect the unit to work without exhaust escaping in the garage?

Thanks.

B.

 

[Duetech]

Hi Blennophobic,
Welcome to the forum! I have a "40" with 6" and have not had a problem with draft. To qualify that though I have to ask if your chimney is single, double or triple walled? The more walls usually means better draft. My set up only has one 90 and then a 22 1/2 that goes straight through the roof and all of it is triple walled and I have had it running for three heating seasons and do the dhw in the summer too. Definitely learn to load only when down to coals or build a smoke fence (the flue outlet is about the same height as the door opening and the open door is just too easy for the smoke to come out, always have the flapper/draft by pass open and shut the boiler off when loading. The puff was from flammable gas that was built up in the loading chamber which means that you were too early on the load or you had too much fire going when you tried to load. Try opening the by pass damper, then shutting off the boiler and let the blower stop and then open the secondary chamber and let the unit set for a few seconds (about as long as it takes to get an arm load of wood) as the method for loading. Try to avoid loading while the unit is up to peak temp as well when there is still half a load in it.

Some have complained of a burn in odor problem. I don't think I had one though.

Do a search for "induced draft" and "EKO smoke" in the "search forums" window in the top left of this page you should find a lot of discussion that will help you. Some use old stove hoods with fans to cut the smoke at loading.

 

[taxidermist]

WElcome,

This time of year it is hard to get a good draft. Also the unit will idle a ton because of no demand for heat and if you open it to fast you will get a puff back. I am sure you have a leaky seal around the door on your eko.......most of us have! You could adjust your door hinges and also search here for sealing your door as we had to seal some spots with high temp silicone. As for your barometric damper did you set it with a manometer?? I found a huge difference with setting it by the numbers on the weight and then setting it with a manometer. See my vid in my sig.

Hope this helps,
Rob

 

[WoodNotOil]

Cave is right on with the smoke being becuase you are trying to load too soon. Don't be afraid to walk away from it and just let it burn. If you have to open the door when the load is new, then open the bypass and leave the fan on for a minute. That will empty the chamber of gasses and you won't get the puff. You will still get smoke however.

The best solution for you would be to put in a draft inducer. Check out this thread and this link for one that some have had success with. That would solve your problem with smoke on loading and help with overall draft problems.

Since your only using single wall chimney, there is a chance it is getting hot and causing problems where it goes through the roof. Check the temp of it. You may need to put in double wall. I know there is supposed to be a burn in smell, but should go away. Read the tuning an Eko sticky really well as it addresses a lot of this.

 

[Fred61]

When I first started my unit, I had an odor that smelled like beef jerkey but it quickly subsided. There has been some discussion on this forum lately about dust forming on surfaces within the vicinity of their boiler. I believe dust and smoke escapes from the joints in single wall exhaust pipe. I learned when operating the Wood Gun, that all joints in the smoke pipe should be sealed with high temp silicone rubber.

 

[stee6043]

As stated above I'm not sure anyone get's "great" draft this time of year. I know I sure don't. I'm running an EKO 40 with 6" pipe and my sweet-spot for draft seems to be when it's 20 degrees or so outside. When we were in the 50's last week I was not getting much draft at all.....which is why I'm now done burning wood for the year!

 

[Blennophobic]

Thanks for the replies! I'm really glad that nobody said I need to go with 7" chimney... that would be expensive after investing in the 6" insulated SS chimney. The graph in the EKO book (love their attempt at English translation BTW) indicates a 7" is recommended for my situation, but I just couldn't see why that was necessary... until now, I guess it would improve my smoke situation.

I like the idea of a putting in a draft inducer for loading. If that gets rid of the smoke I'll be very happy. I'll seal up the chimney joints in the garage and work on better door sealing too. Hopefully this will clear things up.

B.

 

[Blennophobic]

Some pics of my installation... note temporary wiring on pump.

I really wish I could get rid of that chimney offset on the eve, but I hate to cut into the roof overhang.

I haven't lined my storage tank (cistern) yet and it's already started to seep through a small crack. I'd like to put an inch of polyiso insul board in it covered with EPDM but I can't find a source for a small amount of EPDM. I called a commercial roofing place and they would only sell me a full roll at ~$3000. Any suggestions?

Thanks.

B.

 

[WoodNotOil]

You are looking for a firestone pond liner like these http://www.bestnest.com/bestnest/pond_liners.asp . That is what I used. Get a piece large enough that you can just lay it in and fold the excess in the corners instead of trying to seam it. Measure down the sides and the length and width of the bottom. Your piece should be 2xside+length in one direction and 2xsides+width in the other. Check out my webpage in sig for how I did mine. Also, you will want a high R value to hold heat well, so if the polyiso is your only insulation, I would suggest using 3-4" of it. I used 3" on the bottom and sides and 4" on the top. Nice looking coils! Just put in a draft inducer and you shouldn't need to change your chimney at all and you won't have to worry about low draft in off season.

 

[stee6043]

Quick question - what size pipe are you using on your near-boiler piping? Also.....I think the Taco manual suggests you should not mount the pump in a direction that puts the electrical connections on the bottom. You might be better off rotating your pump 180....

 

[Blennophobic]

Thanks for the pond liner idea, I didn't know that was the same stuff. I found a nursery supply that stocks it locally.

Stee, I used 1-1/4" copper for my primary loop from boiler to storage. The secondary loops are 1/2" with their own pumps. Thanks for the tip about the Taco... I thought I read the instructions thoroughly but I see I missed the bit about not mounting the electrical box in the 6 o'clock position.

B.

 

[taxidermist]

I tried many things to fix the smoke out the door and contacted many people who installed draft inducers and everyone said dont waste your money just learn how to load your boiler........so I did and very little smoke now. I am thinking about making a draft inducer like the biomass 60 has on the back of the unit and see how that works. seamed to work ok on the unit I worked on. The one that you cut into the pipe did not work worth beans.


Rob

 

[larry4406]

Off topic but I hope you have finished taping all of the drywall joints in the garage so that you have an appropriate fire rating. In my area, garage walls/ceilings common to living areas need to be 5/8 1hour rated board with taped joints.

 

[Tarmsolo60]

will you be able to put some sort of lid on you cistern after you line it so all your hot water won't evaporate?

 

[Blennophobic]

Rob: thanks for your take on the draft inducer. I'll be interested to hear if you make one like the Biomass has. Do you know what kind of fan/motor to source? I finally got around to watching your draft regulator vid. I'll likely make up a simple manometer next season to set the regulator so long as I get enough draft in the cold weather to open my damper. Looks like you used 8" insulated chimney straight off the unit. I bet that's giving you great draft. My brother has a EKO 25 with a 7" chimney setup similar to yours and he couldn't run it without a draft regulator because it overheated the boiler when the house wasn't calling for heat.

Larry: I'll get to the taping sometime this summer. My building inspector/WETT certifier didn't say anything about 5/8" drywall, only that I would need 2 layers of cement board next to the boiler.

Tarm: So far I've had good success by simply laying sheets of foil-faced polyiso foam board on top of the cistern... cut to fit snugly around the supply/return pipes. I plan to throw a few pounds of paraffin wax into the cistern to help seal in the vapour. I experimented with a couple of bricks of wax and they melted and spread out nicely when the temp got above 52 degC. Actually, if I can find a cheap source of paraffin, I might throw in a hundred pounds or so to increase the heat storage using the latent heat of melting. The phase change temp of paraffin is right in the sweet spot for our systems.

B.