Creosote

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wantageNJryan

New Member
Oct 29, 2013
19
wantage nj
Hi everyone....i am new to burning and jumped in head first with a pb105. I have 2800sqft im heating and have plumbed in my unit in series. Ive run about 15bags or so through the unit without a hiccup. I came home last friday from work and found a horribly smelling home!!! My units burn box tarred itself completely over!!!! So after of relentless scrapping and praying for the tar to lossen up i cleaned the entire burn box in about 15hrs!!!!!
So now im trying to understand what i did wrong. I went through my install step by step and came to the conclusion that i ran out of air since my fan was gummed up. I also did not have the low speed fan set correct. So now with all that behind me here are my specs:
-Hammer Hot Ones premium pellets
-185 max with OAT and OAK
-165 min temp
-.87" wc high speed
-.3" wc low speed
-1 right angle flu pipe and about 4'6"' vertical and 2' to outside and end of pipe
-wantage nj 780ft above sea
-low to zero humidity
-avg daily temp over the last week 55*f
-full southern exposure no trees!!!
-cleaning fan burn pot burn box and ash daily now
-burning 2bags a day
-flu pipe spotless no tar just a lil soot powder...

With those specs i still seem to be building a
Stage 3 creosote just on the wall immediately above the burn pot.... Is this normal???? I dont tar up any of the heat exchange pipes. There is powder soot on them and the fan blades daily but nothing close to the tar i fought over the weekend. What am i doing wrong????

Here are some pics....rotate em 90* clockwise....you can see a definitive line above the burn pot where there is spotless metal and then dripping tar!!!! This photo was 2hrs after cleaning and was still revovering the system temp back to 185 after being idle from cleaning so it should have been f#$%&ing hot!!!

Please help!!!!! If anyone has any super ideas please even call me! Is this even normal???
9732776868 IMG_20131029_224910.jpgIMG_20131029_224830.jpgIMG_20131029_224915.jpg
 
Every wood boiler including the Harmon PB105 requires a return water protection valve, loading unit, that maintains the boiler return water above 140 to 150 F. That would be the first thing to check, if you have a return water protection scenario and is it working. What is the boiler return water temp.

That seems to be what you're describing. The other usual souce of creosote is idling or turning off the fire during the part of the burn were the fuel has a lot of the volatiles remaining in it unburnt.
 
I haven't checked the return temp, but I can only suspect it is well below 140*F as the temp return is coming from stagnant / cold zones....

So sorry for being stupid....no matter what all, pellet boilers require return water at 140*F??? / otherwise you'll get what I see?
 
I googled the manual.

On pg.16 ('Installation' page): Note: Cold return water temperature (sustained temperatures below 140 degrees farenheit) will lead to condensation in the firebox. This moisture can lead to creosote formation. To help minimize moisture and creosote, it is strongly recommended that some form of temperature balance is incorprated into the return water system.

And within the diagram immediately above that: Also shown but not necessarily needed is the boiler bypass line. The necessity of this line will be determined by the installing certified plumber or hvac contractor.

Not sure who sold you the boiler, or who installed it - but if installed by a pro they overlooked it, and if you bought directly from a dealer, they neglected to point that rather important item out. Seems to me to be quite an over-casual way to cover such an important detail in the manual.
 
THANK YOU!!!! I definitely missed that! Appreciate your patience with a city guy gone redneck.... Sorry for the dumb question. I def did not install a mixing valve....
 
I closed that window now, but there was a 3 way mixing valve shown in a couple of their diagrams. It was shown at the top of the bypass loop - I think I'd put it at the bottom, just before your return hits your boiler inlet. And put my boiler circ between that & the boiler inlet, so it can pull through both sides of the mixing valve. But that's without knowing how it's all plumbed now - something a bit different might work also.
 
If you are getting creosote in the PB105 it usually means you have an air leak. I doubled up the gaskets around my ash pan, hopper, and the other small door above the ash pan. In addition I ran a bead of silicon around the base of the boiler where it meets the ash pan.

Once I did that my creosote issues disappeared.
 
Thx to both of you..
Andrew i read your other thread and have some foam tape to put around the seals tonight. Do you have the mixing valve installed??? What brand or model valve should i use? Right now my pellet boiler is in series with a propane boiler. Pellet boiler first in line then plumbed into propane as a failsafe.
Im definitely going to find thw mixing valve. Looking online now...open to suggestions! Thank you all for the help!!!!IMG_20131028_221909.jpg
 
My system is set up in parallel and a mixing valve wasn't needed. Make sure that you use rope gasket and not a foam gasket. I picked my gasket material up at a local hardware store. So it shouldn't be hard to find.
 
Any luck with getting rid of the creosote?
 
Not yet Andrew....I got sick of scrapping and I don't want to damage her any more so right now PB's on temporary shutdown!!! I had to switch back to propane for the time being. I ordered a Califfe ThermoBloc manifold / tstat / circ pump all in one... It was a bit pricey but they seem to be the only company that specifically have designed a recirc setup with BioMass boilers in mind. They're built to order and I ordered it on Thursday last week so I hope to have it soon! I can't wait to accurately see how much more efficient the pellet boiler is compared to the propane unit! I'm hoping to be under $15per day for running pellets!!!

Just out of curiosity, how many bags per day would you think I'll burn running an avg temp of 68*F? I don't know anyone else in my area or even in north jersey running this boiler? Everyone around me uses wood or just a plain pellet stove so I don't have anyone to compare fuel usage with! Do you have any figures on what you burn? I have a 10year young center hall colonial w/ finish basement at 2800square with a full southern exposure, no trees at all...what would you think I'll run through? House seems to generate and hold heat well in the sun!
 
You sprung for a full-meal-deal loading unit. They work very nice - and yes they are pricey. Mine is an LK810. I see the Callefi uses a Wilo pump - the LK uses a Grundfos. I was kind of wondering a while ago if one was made that uses a VS delta-T pump, like a Taco Bumblebee. Seems to me that having the pump ramp up & down with the heat output of the boiler, maintaining a constant deltaT as the fire builds then goes out, might have some benefit? And maybe save a little bit of electricity too.

$15 a day - I thought that was a lot when my parents found out that's what it cost them for oil with their new Buderus boiler last year. How much is it costing you for propane per day? Or is it the $15?
 
maple...this is a new home for me and the first shot at being an educated red neck! I've never paid too close attention to price per day until now. I had natural gas to my last home and now in the new home I only have propane with an introductory price which will ramp up on me! Fearing that, I installed the pellet boiler but I have zero experience with any pellet fuel! The first two weeks I used the boiler (without the recirc pump) I was running through 3 bags a day!!! Made me a bit nervous because it wasn't that cold yet. 15$ came from an avg of $5 per bag or $265 per ton for pellets.... I'm hoping that after i have this recirc setup installed the boiler will be more efficient?!??....

I'm merely looking for any comparison I can get just to see and be able to ballpark tonage. I have roughly 4.5tons of pellets and I was just concerned about getting through atleast until march on that quantity. I hear it is tough to get pellet fuel in North Jersey after xmas so I was debating getting another ton or two just in case! Hence looking for comparison numbers...
 
I averaged about 2 bags per day but I don't know that you can do an apples to apples comparison between different houses since there are too many variables to consider.
 
Recognized....quality of build material, insulation, cooking (oven giving off heat)....completely understood. I just was look for a rough figure.

What brand pellet have you had the most consistency with?
 
I prefer 100% softwood pellets. However, the Harman will eat anything you throw at it. I've done 100% hardwood and commercial grade pellets with no issues.
 
Ok so I'm back to square one............ The califfe block and pump assy got canceled. They were taking way too long. The projected delivery date was Dec 20.....so needless to say I canceled the order! I wound up using a Grundfos 3speed circulator with a custom made manifold. I bled the system out and then heated up the PB to about 150*F using the propane boiler. I switched on the PB and waited...and waited....started cleaning (not paying close attention)....waiting........."shhhhhh booom" (noise heard)......freaked for a second and then realized the unit never ignited normally and ignited the fumes in the burn box!............. I shut it down immediately to find un burned pellets in the freshly cleaned tray. So I re-tried a fire up and watched it this time and now it seems like my problem is definitely an air leak!....... The ignition is not occuring at all normally... I guess the igniter gets hot enough to set the fumes on fire but maybe not enough to restart unit from a leak??....... I rechecked my high speed draft and was dead on .8inches.... Reset the unit and let it go again and same thing....ignites eventually from the fumes but not normally............

So that's still outstanding. Since I'm still under warranty I will be calling my local Harmon guys today to let them get their warranty money!....

Next.... after it did fire and run I'm still getting a heavy tar only up agains the hopper wall right above the burn pot. I had tar and the unit temp was 170 and my intake water temp was 150 right on the button.... So I assume for sure now since I have this new ignition problem (which maybe was there and I never noticed it) coupled back to the original creosote and I think that spells out a intake leak somewhere not causing the .8Inches of draft to completely run itself in through the burn pot......... It's difficult to believe though this thing was leaking from being brand new, or better yet developed an intake leak in under 20 to 30 bags of pellets........

Any other opinoins??? I value all of everyone's experience on this PB as I have none and so far it's not been a good one. Still going to make a few phone calls today to get the local guys to come have a look but I don't trust them at all. I don't believe they've sold too many of these in the area.....enough anyway to have gotten into any servicing concerns... They're unorganized for sure, knew alot about the regular pellet stoves but can't say that I was impressed with their knowledge on the PB. Not that mine is any better but experience is everything and you guys here have it!

Thanks!
 
So i came ho.e from work with a renewed hope after talking with harmon and my dealer. Both pointed me to leaks somewhere and stated the starting issue and creosote will go hand in hand because of air fuel mixtures.... I inspected every inch of seal to see if i could tell where it wasnt sealing and i definitely thought it was the hopper door. Closest to the hinge i was able to see the line from where it sealed on the boiler. But on the red knob side you could see on the seal that it was not imprinted as much. So i actually went and got the fiber rope seal from TS and unthreaded about 4' of it. I threaded more threads through the existing hopper seal like threading a needle to make it a bit thicker. I also had some high temp 1/8" thick foam heat seal tape i use at work. I lined the hopper door and ever other door as a matter of fact with the sealing tape.... My results for starting were finally back to normal but in under 15min of running i literally watched stage 3 form in front of my eyes....IMG_20131115_221941.jpgIMG_20131115_223221.jpg
The second pic is 30min running and u can see dripping tar.... Yayaya!!! I get to scrape tar again!!!! WHAT AM I DOING WRONG. anyone want to trade a pb105 for three regular stoves?????
Heres my recirc setup which delivers no less than 160* back to the boiler no matter how many zones are open!!!! Its not cold water anymore....
IMG_20131115_224911.jpg
Oh i forgot to mention that in the hour or so i ran this again tonight it smoked the entire time and smelled horrible outside!..... Im over the novelty. I cant see having to worry about this everyday!!!! Not to mention getting yelled at by the wife because all i donis worry about the new $8500 boiler......
Any ideas??????
 
Im getting better.....i found that the air intake hose was causing some restriction. I removed the intake and now rest it i the hood that covers the feeder. That helped a ton but i still made some tar in the first 15min of running today. My start water temp was 110 so im wondering if thats what kicked up the tar on me. It ran for 2hours and i have a drip or two of tar but nothing what ive seen i the passed. I must be getting closer to an answer!!!!
 
So i came ho yelled at by the wife because all i donis worry about the new $8500 boiler......
Any ideas??????

I did not read the all conversation here, but a couple questions:
Do you have a Boiler condense protection valve in you piping setup?
Or, at what water temperature is your pellet boiler allowed to circulate the water?
 

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If the LK810 loading group takes to long to order, then go for a LK820 valve at 142F.

110F return water temp is way to cold !!!!!
 
It started at 110 because the boiler sat overnight. I did not circulate my propane heated water through the pb over night. Right now i have 185max and 175min set. I have a recirc pump in parallel with the main house circulator so as soon the house pump runs my boiler recirc will run. With all 4 zones turned on at the same time purposely i witnessed no less than 160 on my boiler input now. See pic....IMG_20131115_224911.jpgIm definitely running the proper boiler temps now.

I scraped off the little bit of mess it made from re starting today and im out now so ill see what tonight tomorrow brings....maybe the tar fairy will skip me by!!!
 
Could your outside air tube have been drawing in air from the exhaust vent? They look quite close in the photo.

The flame in the second photo you posted Friday looks lazy to me, like it's not getting enough draft. The 5:06 photo from yesterday looks like the stove is starting to clean up the creosote, though. Do you agree?

If you want to hunt gasket leaks, you might dust around the doors with some talcum or line-marking chalk. Air leaks should clean it off.
 
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