Wood Stove Woes

Posted by: bilvihur

Wood Stove Woes - 02/22/12 07:01 AM

A Vermont Castings Resolute Acclaim, with about 1 cu. ft. firebox, and a 6" flue. I had to do a major cleanout of the chimney liner and flue pipes last month:
http://handymanwire.com/ubbthreads/ubbth..._Cap#Post701801
I attributed that to not burning hot enough due to our mild winter, and subsequently left the air control on high. Well, late last week we began to notice smoke escaping from around the gaskets and pipe connections. frown I let it burn out, and went up on the roof with brush and rods, expecting to find a gooey creosote clog like before. Surprisingly, the brush went all the way down to within 3' of the "T". I went inside, took the cleanout cap off, and snaked upward with a length of BX. I broke up a big clog of solid creosote not more than 4' from the stove!
I couldn't understand why that should happen until I did a close inspection of the stove and found a 1/4" gap at the bottom of the pipe going into the stove flue collar! I suspect this was allowing room air to be sucked in, bypassing the stove, and cooling the flue gasses. I jammed the pipe into the flue collar, placed a few screws, and taped the joint with aluminum tape. We'll see how that works.
Question: Does anyone have a rule-of-thumb about size of logs in a stove. A 6" log has the same amount of wood whether whole or quartered, but the split pieces have more than 2X the surface area, and will burn faster (and hotter). I think a mistake I've been making is trying to burn logs that are too large for the stove. What say you all?
Posted by: Clint_Robbins

Re: Wood Stove Woes - 02/22/12 08:39 AM

It takes longer for an intact log to season than if it is split - maybe that is your problem. If you listen carefully and hear any hissing in the fire, that means there is moisture being evaporated.
Posted by: ront02769

Re: Wood Stove Woes - 02/22/12 08:46 AM

let's see. we heat with wood. put in new stove 2 years back and get at most a half cup of yuck from chimney and inside pipe per year. so you are doing SOMETHING wrong. check all of the connections. don't put one big six inch log in and let it burn. in fact don't put in anything if you can't fit THREE of them in in a triangle. heat it up decently hot once every time you use it. will save you a lot of trouble.

oh well, I am off to the backwoods to cut some firewood for NEXT year. ront
Posted by: bilvihur

Re: Wood Stove Woes - 02/22/12 10:48 AM

The wood is seasoned 2-3 years and not giving off steam. Ront's suggestion of not adding wood that I can't fit 3 at a time is on the mark. It's going to be more wear & tear on my maul and shoulders, though! cry
Posted by: FredDwyer

Re: Wood Stove Woes - 02/22/12 02:03 PM

You mentioned tapeing, with aluminium tape, the flue-pipe/flue-collar connection. I may be way off base here, but it seems to me that while the aluminum is quite heat proof, the gum on the backside may be less so. I'd suggest sealing it with silicone or even furnace cement. Silicone would be pretty easy.
Posted by: ront02769

Re: Wood Stove Woes - 02/22/12 03:51 PM

but it would last only if you use the high temp stuff. other than that, based on where he is putting it, it will just melt. ront
Posted by: jigs

Re: Wood Stove Woes - 02/22/12 05:23 PM

I seal my chimney connection to the stove collar with furnace cement - no problem. Looking at your earlier post pictures you're getting creosote buildup because your piping is not insulated - it's cooling down almost instantaneously; that 1/4" gap you found probably made little difference to the build up. Monitor the temperature of your fire rather than be concerned with the size of your logs. If you have a good bed of embers you should be able to put a tree trunk into the stove without a problem, if you adjust the draft to keep it hot enough.
Posted by: ront02769

Re: Wood Stove Woes - 02/22/12 07:04 PM

issue is a single log burning will never generate enough heat and draft to keep it hot enough. multiple smaller logs will help greatly. and don't 'damp the fire down' when you go to bed or it will produce creosote all night as stack temps drop below like 275 degrees or thereabout. ront
Posted by: bilvihur

Re: Wood Stove Woes - 02/25/12 05:27 AM

So far so good. I've been able to maintain the temp between 300-450 degrees by adding smaller pieces of wood more frequently, and adjusting the air intake. I can bring it to 500 degrees by moving the intake to the start-up position, which I've been doing for 1/2 hour in the morning. I haven't even had to scrape the glass door!
I've also been leaving the ash bed fall through the grate naturally, instead of stirring it up with a shovel. It seems to make the embers last longer (and hotter). laugh
Posted by: CabinConnection

Re: Wood Stove Woes - 02/25/12 05:30 AM

Grate!

(pun intended)

In my fireplace I prefer to let the ashes pile up under the grate, or in the stove I don't use a grate. Helps reduce the uncontrolled draft under the flame, promoting longer burn times.
Posted by: sportster

Re: Wood Stove Woes - 02/28/12 05:22 AM

I start all my fires directly on the bottom of the stove. I used to use a grate but after trying it out without one the fire seems to stay hotter longer.

Not to steer you away from this forum but this one has allot of good info if you want to know more about your stove.

http://www.hearth.com/econtent/index.php/forums/
Posted by: bilvihur

Re: Wood Stove Woes - 02/28/12 06:46 AM

Thanks for the info. I'll look at the site when I have more time. If I remove my grate I'd have a hot fire right in the sheet metal ash pan, with no easy way to empty the ashes. I'm getting good results by letting the ashes accumulate on the grate, only emptying the pan as they fall through naturally.
Posted by: ront02769

Re: Wood Stove Woes - 02/29/12 05:58 PM

there are grates and grates. SOME consider a grate like that put into a fireplace to be the 'grate'. others consider the 'floor' of the stove to be the 'grate'. pulling the 'stove floor' and letting the ash tray fill p would seriously undermine the air flow in most modern wood stoves. ront
Posted by: CabinConnection

Re: Wood Stove Woes - 02/29/12 07:18 PM

Originally Posted By: ront02769
there are grates and grates. SOME consider a grate like that put into a fireplace to be the 'grate'. others consider the 'floor' of the stove to be the 'grate'. pulling the 'stove floor' and letting the ash tray fill p would seriously undermine the air flow in most modern wood stoves. ront

Not entirely clear on what you're saying here... But all the wood stove manufacturers I'm familiar with recommend NO grate. They recommend building the fire directly on the fire box bottom fire bricks. I pretty sure this is what you do as well...

(Grate defined as a metal cradle which raises the wood up an inch or two.)
Posted by: Clint_Robbins

Re: Wood Stove Woes - 02/29/12 07:50 PM

Quote:
all the wood stove manufacturers I'm familiar with recommend NO grate. They recommend building the fire directly on the fire box bottom fire bricks.

I have a Temp Wood downdraft stove with fire brick on the bottom and about half way up the sides. The fire is built on the floor, the wood is loaded through a 10" diameter lid opening in the top, and the ashes are removed through the same opening. When the ashes build up near the top of the fire brick, I let the fire go out during a warmer day and remove all of the ashes. The stove is very efficient and will burn wood, etc. of any size or shape that can be loaded through the opening.
Posted by: ront02769

Re: Wood Stove Woes - 03/01/12 05:36 AM

Here is what I mean In the pix of this stove, the little door at the very bottom in front is where the sheet metal ash tray slides in and out. On top of THAT, there is a built in grate that can be removed. you build the fire on that grate which functions as the floor of the stove. so, burn THIS one withOUT the grate would be a no-go as all air flow is designed WITH the grate. and that is what the OP meant I think. for those who consider a 'grate' to be the little cradle thing that you buy at hd and put in your fireplace, I guess you could go with or without one, but the stove is setup to to withOUT. ront
Posted by: CabinConnection

Re: Wood Stove Woes - 03/01/12 05:39 AM

I think we're all on the same page... smile
Posted by: bilvihur

Re: Wood Stove Woes - 03/01/12 08:44 AM

My stove looks like this:



With "Grates" instead of "Crates", ashpan directly under the grate, and no firebricks on the stove floor.
Posted by: CabinConnection

Re: Wood Stove Woes - 03/01/12 10:05 AM

Leave those "crates" in place.
Posted by: ront02769

Re: Wood Stove Woes - 03/01/12 12:42 PM

Absolutely leave those grates in. that is the was the stove is designed. ront
Posted by: Dennis_H_N.J.

Re: Wood Stove Woes - 03/02/12 12:55 PM

Although I had a Vermont Castings stove for years, I'm no pro... But I did burn a hot fire every so often.. It kept a sweet chimney.. "Gotta" burn hot every so often.. (A little Jersey lingo for ya"!
Posted by: bilvihur

Re: Wood Stove Woes - 03/05/12 05:54 PM

Add chimney sweep to the growing list of occupations where I'd starve if I had to do it for a living! blush Less than 2 weeks after "cleaning" the liner, I began to have the all-to-familiar poor draft/smoke backup problem. This with burning smaller pieces of wood at 350+ degrees. The brush went down effortlessly, only stopping at the final 3-4' that I'd ovalized/flattened to get the liner through the fireplace damper opening. Last time around I ran a length of BX up from the bottom to get this section, but apparently it was too flexible to clean it out well. This time I had a 10' length of 3/4" steel cable and worked it for 1/2 hour. I got a lot of crusty creosote out. The stove is burning fine now at 400-500 degrees. I'm sure that the ovalized section is the choke point for buildup. I'm debating whether to buy another 6" poly brush and trim it down to a 5"x6" oval so I can do the whole job from the top, or just use the cable and hope for the best. confused
Posted by: ront02769

Re: Wood Stove Woes - 03/05/12 07:56 PM

not normal. you have something wrong in the vent stack, chimney wherever. should NOT be getting that creosote in that period of time. ront
Posted by: CabinConnection

Re: Wood Stove Woes - 03/06/12 04:12 AM

"...smoke escaping from around the gaskets and pipe connections."

Is THIS your symptom - what you're trying to fix? Seeing smoke backdrafting? And you're assuming creosote buld-up is the cause?

Most back-drafts are the result of inadequate air supply to the house interior (if you have a firebox that has room air as the source location). Things that impact this are not hot enough fire to cause a good draft, poor stack design above the roof, and/or too tight a house which doesn't allow adequate air flow.

If the fire's even marginally hot (like during start-up even), try cracking a nearby window to provide air.

Also, I'm assuming you haven't had this problem in previous winters? If not, has anything outside changed? (New addition changing your roof line for example?) How about new windows/doors which are tighter? Any building changes since the last time it worked correctly?
Posted by: bilvihur

Re: Wood Stove Woes - 03/06/12 06:09 AM

I hear what you guys are saying, but my stove is cruising at 500 degrees this AM, and the ONLY thing I changed this time was working the flattened section for 1/2 hour with a stiff cable.
I liken it to a drain clog that you poke a hole through. The water drains, but it serves as a choke point for debris to catch and clog up soon again. This is my 2nd year with the liner, and I never cleaned that section from above or below until now. Creosote was probably in there from last year and I didn't know it.
I'll keep you posted.
Posted by: Clint_Robbins

Re: Wood Stove Woes - 03/06/12 07:12 AM

What type of transition do you have from the round flue pipe through the damper opening and back to a round flue pipe? My kit had a transition piece that was about 3" x 10" which provided the same area as the 6" round pipe and I've never had a problem with it.
Posted by: bilvihur

Re: Wood Stove Woes - 03/06/12 08:44 AM

I didn't have a transition. I simply stepped on the 6" liner until I had a roughly 7"x4" oval that would fit through the damper. Then I rounded the end to fit into the "T". Not the most efficient setup, I agree, but if I can keep that section clean by trimming the poly brush to fit, I should be OK. whistle
Posted by: Clint_Robbins

Re: Wood Stove Woes - 03/06/12 08:49 AM

Are your "stepped on" joints tight and well sealed with the male ends pointed toward the stove?
Posted by: bilvihur

Re: Wood Stove Woes - 03/06/12 09:20 AM

Yep! It was a struggle to get it round enough to fit inside the "T", but it did, and I tightened up the screw clamp well. I calculate the oval section has 80% of the cross section area of the rest of the 6" liner, but I now know enough to give it a special cleaning.
Posted by: bilvihur

Re: Wood Stove Woes - 04/04/12 07:32 PM

Almost like clockwork, the stove started smoldering, the heat output fell below 300 degrees, and creosote was dripping into the fireplace. This time, instead of getting out the ladder and rods and brushing from the roof, I took off the clean out cap, and worked my 6' cable up the liner for 10 minutes, removing about a quart of crumbly creosote. 45 minutes later, the stove was humming at 500 degrees. I guess it's something I'll have to live with... frown
Posted by: ront02769

Re: Wood Stove Woes - 04/07/12 01:20 PM

you shouldn't have to live with it. personally, if I had a stove with that issue and couldn't sort it out myself I'd have a professional come in and take a look. creosote buildup of that amount in that period of time is dangerous and can result in the fire that you DO want starting one that you DON'T want. get it checked or don't use the stove. ront