Wall Thimble leaking smoke, Duravent Pellet Vent.

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Merrimack_Pellet

New Member
Nov 26, 2020
3
Merrimack New Hampshire
We just bought a huge house in New Hampshire , hard to heat of course. It came with a fairly new looking Santa Fe Quadrafire.
It has a Duravent PelletVent on the wall. This is a telescoping wall thimble, the inner and outer pieces slide together and allow a wide range of wall thickness. My walls seem pretty standard.

It leaks smoke from inside the wall, obviously coming from Somewhere inside the wall thimble. Any thoughts? I am new to this.
Here is a link to the wall tmhible instillation guide for my model.
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Sounds like when the install was done who ever done it has a pipe joint in the thimble, You will need to take the vent system apart and see if this is the case and if so get a proper length of venting to eliminate the joint in the thimble.
 
Good morning & welcome to Hearth.com.
First, I changed the spelling in your post from
"tremble" to "thimble."
If you have a leak IN the thimble, you must have a
pellet vent joint in there. The only way to see, is
to pull the venting out. You will probably have to
cut through some silicone on the outside in order
to move the vent. You may have to move the stove,
away from the wall, as well, if you can't unlock the sections.
Once you pull the venting through, may sure the connection
is tight & wrap it in some aluminum tape to seal it.
Before you push it back in & re-silicone the outside, fire it up
& make sure the joint is sealed.
 
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OK, with winter approaching I dont want to do a major repair if I can avoid it. That said the stove does not have the cold air intake connected to the outside so I am waisting indoor air for combUstion. They do sell an identical thimble except it has a wall plate/thimble with a feed through for the cold air so I can swap it out with minimal eFfort.

But what I am getting here is that I can disassemble it, wrap the interior joint with metal tape and have a fairly cheap fix for this winter?
I am looking for the wall thimble I need at a decent price.
 
As both stated above. You NEVER have a venting joint inside the Wall thimble., It must be a continuous length of pellet venting, which of course is available in various lengths from a foot to 6 feet long. www.ventingpipe.com will have what you need if a local supplier don't.. Please understand however that there are 2 different and unique styles of pellet venting and they DO NOT interchange, Simpson Dura-Vent and Selkirk so you need to determine which brand you have and order accordingly. Determination is easy. There should be a label on at least some of the pipe sections as to the brand, be sure to get the same brand.
 
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Not dangerous but stinks I'm sure. In reality, a biomass stove when running at operating temperature produces no visible smoke at all, which is why they are so efficient but, you can still smell the 'smoke' (if you want to call it that), what you smell is invisible to your eye particulates, which brings me to another point and that is..

Did the previous owner maintain the unit? Biomass stoves all produce fly ash and a bit of soot when operating. consequently, the venting needs to be cleaned regularly, the stove interior (firebox) needs to be cleaned and the flame path around various baffles also needs cleaning as well as the draft path trough the combustion blower. Was it maintained or not? If you don't know, clean it and if you don't have a manual, contact the manufacturer and get one or download one from the net and read it and operate the unit according to what is says. The stove builders always know better than you, they built and designed it.

I'm sure you'll have questions. The operating manual will answer most (if you read it) and any others, post a question on here, but follow the operation manual. Most of the questions posted on here will be addressed in that manual, but you have to read it and follow it.

Finally, don't expect ANY biomass appliance to be a primary heat source ever. They only provide SUPPLEMENTAL heat and relieve some of the heating load from your central furnace. They are not meant to be a primary heat source as the BTU output of any appliance is much less than the heat output of your central furnace.

To assume it will will leave you cold and shivering when the outside temp is below freezing.
 
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thanks. As I said I am completely new to this. Its leaking little bits of smoke from the edges of the wall plate. So you are saying this is very bad? Dangerous?
In my opinion, no smoke at all. No joint, sealed or unsealed, in wall thimble...
"SidecarFlip" is correct first read the manual, it covers install, maintenance, etc..
 
If you could post some pictures or a video of your setup, it would simplify everything.
 
I agree you’re not supposed to have a joint inside the thimble in any case. Considering you’re pulling that smoke inside the house, you’re getting negative pressure, and would benefit from the addition of the outside air kit to relieve that pressure. With negative pressure if you fix the thimble with a solid pipe you might start pulling smoke from somewhere else. Mine actually pulled smoke through the factory riveted seams in the pipes. Also like you said you’re wasting your heated air for combustion. Would be nice to solve it all at once.
 
Leaking smoke ? No way I would leave that be, need to find out if joint or other problem, one never knows what a prior owner did or covered up. Never put a joint in an enclosure like a wall thimble/pass through.
 
Does your flue pipe go outside,and then up? if it does,you have a serious issue.If it goes outside and ends not very far from side of house,AND if the wall thimble was not sealed/installed properly,your stove could be sucking in the normal fumes.If just goes outside and ends,it should be 12" minimum from the exterior of the house,for most stoves/codes. If you have doubts/more questions,post inside and outside pictures of your flue.
 
I agree you’re not supposed to have a joint inside the thimble in any case. Considering you’re pulling that smoke inside the house, you’re getting negative pressure, and would benefit from the addition of the outside air kit to relieve that pressure. With negative pressure if you fix the thimble with a solid pipe you might start pulling smoke from somewhere else. Mine actually pulled smoke through the factory riveted seams in the pipes. Also like you said you’re wasting your heated air for combustion. Would be nice to solve it all at once.
Hmmm.. Last time I checked, the outer jacket on both the Duravent and the Selkirk has a Chicago (interlocking) seam, no rivets anywhere.
 
Hmmm.. Last time I checked, the outer jacket on both the Duravent and the Selkirk has a Chicago (interlocking) seam, no rivets anywhere.

My duravent has rivets on the elbow and tee sections. I have a 45 in the house.
 
My duravent has rivets on the elbow and tee sections. I have a 45 in the house.
The only way they can secure the angle cuts to the collar but they do not perforate the inner stainless liner at all.
 
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