Novice concerned with creosote

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ptgilland

New Member
Hearth Supporter
Nov 12, 2007
15
Central New York
I recently installed a pre 1990 Vermont Casting Resolute. I have a 17' chimney, 11' of it is class A double wall. The interior portion typical single wall. All straight shot with no bends, and it is 6" diameter. I

When the stove is running and warmed up, and I put it into updraft with fresh wood, I let it burn hot for a period before putting it into the side draft mode. Letting the thermometer on the stove top run upto 550 to 650. The problem is after a few minutes (not everytime, but frequently) we smell something strong. I assume it's creosote burning, although we see no smoke, and the smoke detectors in the house go off.

Whether this happens or not, I do hear in the stove pipe a sizzling sound that occurs once I switch to the side draft or open a stove door. I assume that is the creosote cooling. After letting the stove cool I looked inside and up the pipe. The inside of the pipe has about and 1/16th to 1/8th build up of creosote. It is rough looking, but alittle shinny.

Is this normal for this stove, or should I be concerned. I had searched for clues in the Q&A;section for a while, but thought it might be best to pose the specific questions here.

Thankyou,
Pete
 
I am not familiar with that particular stove but it does not sound normal. You might hear some expansion from heat and the smell you speak of may be just the paint from the stove pipe and the stove. Hopefully you did a couple of slow burns which would have taken the smell away from the stove but the pipe needs a little more to get rid of the smell. Our last one took probably a month to get rid of the smell from the pipe when it got hot.

That chimney should be enough for what you have and being as how you have creosote, I'd suggest you have a problem with unseasoned wood.

btw, it is a good idea to check that chimney 3 or 4 times per season and clean as necessary.
 
I would check the chimney from above, if possible. Near the top, where the chimney comes out of the roof, is where you're most likely to see a large creosote buildup, if it's happening. Then you can adjust your burning practices accordingly. Burning creosote has a pretty distinctive smell. I agree with BWS's point on the pipe--this stuff all times some time to break in.

What kind of wood are you burning and is it dry? How old is the black pipe connecting your stove to the chimney?

Serious creosote buildup will eventually restrict your draft to the point where you get a face full of smoke every time you open the stove door. If that's not happening, it's probably not the problem. But just as a matter course, I'd check the chimney. In fact, if it's a straight shot, you can just look right up and see if it's getting clogged. The amount of creosote or fly ash you described doesn't sound to me like cause for alarm.

Safety note: wear safety glasses when looking up a chimney, or use a mirror.
 
In some ways what you describe can be good - to burn off a thin layer in the pipe before it gets too heavy. Also, what I have found in many cases is that once the interior of the chimney is coated with fly ash and burnt creosote, the "tar" is less likely to build up. So new pipe is more likely to have those mini-fires.

I think the smell may partially be the paint curing from your pipe. Creosote smells like smoke, while curing paint has a bit of a chemical smell. If it is a creosote smell, check for small leaks of moisture and tar from the pipe joints and even from the bottom of the stove. Make certain a layer of sand or ash is in the bottom of the unit.
 
[quote author="Eric Johnson" date="1197325845"]I would check the chimney from above, if possible. Near the top, where the chimney comes out of the roof, is where you're most likely to see a large creosote buildup, if it's happening. Then you can adjust your burning practices accordingly. Burning creosote has a pretty distinctive smell. /quote]

what does burning creosote smell like?
 
Thanks for all the responses. I'm not that familiar enough to be able to tell the moisture content of the wood myself. I bought it from a friend who said it was well seasoned. I think it is mostly hickory, definetly hardwood.

I tried solving the problem of any smoke coming through the joints of the stove pipe by taking it apart and putting back together with black furnace cement. The only unsealed joint would be where the stove pipe adaptor and double wall twist lock together. On only one occassion after doing the furnace cement, I did notice a small amount of smoke coming from that connection. I took it apart and twisted back to together slightly tighter. I had used screw originally, but changed to the locking ring that came with the kit. I thought that would do a better job, and it seemed to until the detectors went off again this morning.

Even though this stove says to monitor temps from the stove top, I can't help think that perhaps the flue temp is to low when in side draft. I was going to get another temp gauge to stick on the stove pipe. Any recommendation as to how far up from the stove to place it? I know that question gets asked often, but I havn't seen anything decisive on that.
 
karl said:
Eric Johnson said:
I would check the chimney from above, if possible. Near the top, where the chimney comes out of the roof, is where you're most likely to see a large creosote buildup, if it's happening. Then you can adjust your burning practices accordingly. Burning creosote has a pretty distinctive smell. /quote]

what does burning creosote smell like?

It's hard to describe, but I would characterize it as a heavy, industrial pollution smell, vs. what most people associate with wood smoke. Maybe somebody else with more facility with the language can do a better job of describing it.
 
Creosote stinks to high heaven!

Not pleasant like some whiffs of wood smoke or pellet exhaust.

If the flue temp goes too low in side draft, it indicated a lack of draft, or enough coals, or wet wood, etc.

Many folks with early VC's were unable to burn them in side draft in certain weather since it requires a strong chimney to suck that smoke all around the baffles.
 
ptgilland said:
I recently installed a pre 1990 Vermont Casting Resolute. I have a 17' chimney, 11' of it is class A double wall. The interior portion typical single wall. All straight shot with no bends, and it is 6" diameter. I

When the stove is running and warmed up, and I put it into updraft with fresh wood, I let it burn hot for a period before putting it into the side draft mode. Letting the thermometer on the stove top run upto 550 to 650. The problem is after a few minutes (not everytime, but frequently) we smell something strong. I assume it's creosote burning, although we see no smoke, and the smoke detectors in the house go off.

Whether this happens or not, I do hear in the stove pipe a sizzling sound that occurs once I switch to the side draft or open a stove door. I assume that is the creosote cooling. After letting the stove cool I looked inside and up the pipe. The inside of the pipe has about and 1/16th to 1/8th build up of creosote. It is rough looking, but alittle shinny.

Is this normal for this stove, or should I be concerned. I had searched for clues in the Q&A;section for a while, but thought it might be best to pose the specific questions here.

Thankyou,
Pete

We have a VC Defiant circa 1975 and the sizzling sound is soot and possbly creosote burning off the flue. Burn the stove hot at least twice a day. Check the primary and secondary air intakes for fly ash, we blow them out (doors closed) weekly. We use a flue cleaning compound weekly and clean the flue 3 times a year.
There are some good tips in the manual:
(broken link removed)

Since it was damp and low barometer lately, you may be experiencing some back puffing. This could be because of clogged pipe or possibly a clogged spark cap/arrestor so check that out too.
 
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