What's going on with my Central Boiler CL5648?

[Jon_E]

Got problems. Not sure if it's me or the condition of the boiler. This winter's been tough and lately I've been having to burn wood that has only been seasoned 6 months. Generally frozen and a lot of steam and boiling off the ends when heated. The boiler itself has a cracked door, new one on its' way under warranty from Central Boiler. Also, my door gasket is in rough shape, also have a new one of them but have been waiting for the new door.

So the problem has several symptoms. First, when I feed the boiler, no matter where I place the splits, no matter how many coals are in the unit, I get a crazy amount of smoke coming out of the door into my face. I have to duck down and feed the thing from a crouch. If there's a lot of coals it's better but not much. It never used to be this bad. Also, when there is a good roaring fire, I used to get a massive plume of smoke/steam out of the chimney (2 sections of 8" double wall stainless) and then it would quickly turn white and then on a full burn, it would disappear, although if you were up close you can see the intense heat coming out of the chimney. Now I get this weak plume of smoke, looks like it is coming out of a 4" stack, and it's really lazy, not intense like a forced draft would be. I used to get chimney fires that looked like a 6' high jet of flame coming out of the stack and sounded like a train. Now I can't even force one.

Also, I am getting these giant puddles of sticky soupy creosote all over the bottom of the door opening, they are getting all over the door and even dripping out of the door. I also get a backdraft of smoke coming out of the door damper (never happened before) and even some wisps of smoke coming out of the box on the side that holds the propane burner (it's a dual-fuel model).

I have a feeling I am not getting nearly enough draft in this thing. The only thing I can think of is that my chimney is so full of creosote and other crap that it simply isn't drawing enough air through the unit. I also wonder if it would be wise to add another section of chimney (I have 8 feet - 2 sections) to get a better draft.

Any advice? I'm planning on cleaning this thing out over the weekend, but other than a possible obstruction in the chimney, nothing has changed in this boiler since it was installed.

 

[ihookem]

Do you think you might have a water leak??/ Or maybe it's just the wet wood. Either way, it seems like a lot of moisture.

 

[2diamond]

Do you have a access panel at the bottom of the chimney ?

 

[Smoke Signals]

Hows it heating?

 

[Armaton]

Is your bypass/diverter opening when you load? Shouldn't be getting that much smoke out the door if it opens and lets the flames/smoke go straight up the chimney. If it isn't opening, it probably has caused you to have alot of creasote in the chimney that can't burn off. I also knew someone that swapped the output and return lines, and the stove acted like that, was just drawing the returned colder water back into the output and had creasote pooling in the burnchamber because the burnchamber and chimney could not get hot enough.

 

[jebatty]

I understand your need to burn unseasoned wood. But as you know, burning water does not provide much heat and has lots of undesirable side effects, which appear to be the cause of most of your problems. Get way ahead on your wood for next year and following. Two summers of seasoning likely would solve your issues.

 

[Hydronics]

Green wood is certainly an issue. I would check your chimney, it is likely constricted by creosote build up based on the lack of draft you describe. This would certainly compound the issues you are having. If you add more chimney it is likely to get plugged up sooner as the gasses cool and condense further as they pass through.

 

[maple1]

Green wood = you're putting 3-5 gallons of water in the firebox for every 100 pounds of wood (depending just how green it is). Plus whatever snow & ice is frozen on it. If your firebox holds 10 cu.ft., roughing in at 50lbs/cu.ft. of wood, that's 15-25 gallons of water per firebox load. You can adjust the numbers to fit the situation (I just pulled some rough ones out) - but it would still add up to trouble in more places than one, and likely all that you're seeing. Sounds like you've got big creosote buildup for starters, & flue is likely plugged up.

 

[Jon_E]

Hey thanks for everyone's comments. This is an old-school pre-EPA unit, so the only thing that is mechanical in the draft "path" is the damper on the door. There's no smoke diverter.

I am sure that poorly seasoned wood is a root cause for the problems I have. However, I don't have really any other options besides switching this thing over to propane and waiting until spring. Even worse, I have nothing for next year - I only have about 4 cords on the ground in tree length or rounds, and it's all literally on the ground and covered in 30" of snow. I'm going to be spending all summer cutting wood to get ahead.

I took the day off today to see if I can get to the bottom of this. Hopefully it's just a lot of built-up gunk in the chimney and I can clean that out and restore the draft.

 

[Smoke Signals]

Can you find some old pallets to burn to get you by until you have better wood?

 

[goosegunner]

Green wood = you're putting 3-5 gallons of water in the firebox for every 100 pounds of wood (depending just how green it is). Plus whatever snow & ice is frozen on it. If your firebox holds 10 cu.ft., roughing in at 50lbs/cu.ft. of wood, that's 15-25 gallons of water per firebox load. You can adjust the numbers to fit the situation (I just pulled some rough ones out) - but it would still add up to trouble in more places than one, and likely all that you're seeing. Sounds like you've got big creosote buildup for starters, & flue is likely plugged up.

Checked the specs,

56 cu ft firebox

gg

 

[Jon_E]

Can you find some old pallets to burn to get you by until you have better wood?

Yes, but probably not enough. I have a stockpile of new pallets for stacking my wood on but I really don't want to burn new pallets.

 

[Jon_E]

Do any of the available chemicals work, such as Rutland's Creosote Remover?

 

[maple1]

Checked the specs,

56 cu ft firebox

gg

Holy crap, that's huge. Mine is only 3.

Re. the chemicals, not likely (IMO).

 

[Jon_E]

Follow-up on my post, just in case it ever helps someone else. I bought a few of those small "creosote bombs" made by Rutland, and threw a box full of them (3) in the hot fire yesterday. Today I pulled the cap off the clean-out tee at the back of the wood boiler, and the tee was packed full of dry creosote. I mean full. A mix of black flaky stuff and dry gray powdery soot. I scooped it all out and swept the pipe clean. My clean-out cap was in rough shape and fell apart on me, needed replacement, so I drove the 45 minutes to my Central Boiler dealer and bought a new cap. I asked the dealer what type of brush I should use to clean my chimney - wire or poly. He looked at me funny and asked me why I would clean the chimney of a outdoor wood boiler. I replied I wasn't getting any draft. He said that what he does, is get up in a bucket truck and look inside the top of the chimney, usually there's a mass of hardened flaky creosote (stage 2 and 3) at the very top of the chimney and he simply chips it out. Well I don't have a bucket truck so I took some chimney rods and a smaller brush and slid it up the chimney, sure enough my chimney was plugged up tight, probably only had a 2" hole in the mass of dry creosote. It all came falling back down the chimney. Well I noticed a vast improvement right away, the boiler is back to doing what it is supposed to.

I think the problem I had is unique to the circumstances. The creosote is forming in larger quantities than normal because I am using not-quite-seasoned wood, and because of the long spell of very cold temperatures, the liquid creosote tends to solidify around the door and the top of the chimney. I actually saw some snow on top of the rim of the chimney the other day, in spite of there being an active fire in the firebox, and that was a clue that the chimney just wasn't getting hot enough. I tried to force a chimney fire with a big pile of cardboard and pine scraps but it's just too cold to get the thing roaring. I'll wait until spring, take the chimney off, and clean it good.

 

[laynes69]

What you experienced will happen with either seasoned or unseasoned wood. It's the nature of the beast. Incomplete combustion when the boiler idles will cause creosote. If you had stage 3 glaze, a single hot fire will cause the stuff to expand and block the chimney. The colder weather is better, it works the boiler and things should remain cleaner. I don't have an OWB, but would think that loading only with what's needed will help keep things cleaner. The more wood that's loaded when it idles, the dirtier it will burn.

 

[heaterman]

I'm sure that it's making literally buckets of liquid creosote from what you describe.
About all you can do at this point is keep the chimney clean and split the wood to about 4x4, 4x6 size to help with the combustion problems.

 

[Jon_E]

I'm sure that it's making literally buckets of liquid creosote from what you describe.
About all you can do at this point is keep the chimney clean and split the wood to about 4x4, 4x6 size to help with the combustion problems.

Yeah, I'm tending to agree - although after cleaning that blockage out of the chimney I noticed that for the past couple days there has been no pooling of liquid creosote around my door, and there is a lot more gray/tan sooty material rather than black glossy flakes, accumulating in the firebox. The burn times are also much better, even with -23 degrees last night. I cut all my firewood to 20" and generally split small enough to grab the end with a gloved hand, so the wood definitely has a good chance at being dry if I would only give it the opportunity.