help with leaks and smell...

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carboncow

New Member
Jan 8, 2015
9
Central Ohio
Got a pellet stove last week...runs great but smell was pretty strong of wood. Did lots of reading and determined best ways to test for smoke was one the stove is first fired up (from cold) and in the dark...bingo...look at all that smoke!

I am using duravent and many (on the internets) state high temp caulk is not needed due to the quality of their connections but that obviously is not true. We took the duravent off, caulked every connection and then wrapped those connections/joins in 3M high temp tape, but...

We have two 45 degree angles in the house...it had to happen. I've now noted that the smoke pours from all the joints in the 45 where they have crimped to make the angles...not at the junctions I created.

So we added more tape...basically covering the duravent at each joint...but I can STILL see smoke when cold. I have not fully tested running hot and long because I want the caulk to cure over night. Why am I still seeing smoke!?!?

How many times can I wrap this thing with tape before seeing no smoke results from the crimps in the angles? Any other solution to get rid of that start up smoke leaks (that lead to leaks you don't see but smell later). Or is this something I have to live with that they "do it" a little when cold?

Again maybe many of you don't have this because you go straight out from your stove thru the wall but obviously those going through the roof will have one 90 and in my case to 45.
 

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You need to let it get hot, once hot it will seal it's self through expansion now that you have wrapped the joint's. If you still see smoke after an hour or so, replace that section of pipe for a new one, or re-wrap it with the tape (take old tape off first).
 
Thanks. I never saw smoke before after hit got (only during the cool period) so I doubt I will see it now that I've caulked and tapped...and although smoke (visually) never found a way thru those joints we can smell a very strong wood smell.

Are there better tapes on the market then the 3M or is that they only option out there? Anything more flexible that I know will seal better.
 
3M is the best out there that I know of.

When the pipe is cold it will leak for a short while, once hot it will seal it's self.
 
Got a pellet stove last week...runs great but smell was pretty strong of wood. Did lots of reading and determined best ways to test for smoke was one the stove is first fired up (from cold) and in the dark...bingo...look at all that smoke!

I am using duravent and many (on the internets) state high temp caulk is not needed due to the quality of their connections but that obviously is not true. We took the duravent off, caulked every connection and then wrapped those connections/joins in 3M high temp tape, but...

We have two 45 degree angles in the house...it had to happen. I've now noted that the smoke pours from all the joints in the 45 where they have crimped to make the angles...not at the junctions I created.

So we added more tape...basically covering the duravent at each joint...but I can STILL see smoke when cold. I have not fully tested running hot and long because I want the caulk to cure over night. Why am I still seeing smoke!?!?

How many times can I wrap this thing with tape before seeing no smoke results from the crimps in the angles? Any other solution to get rid of that start up smoke leaks (that lead to leaks you don't see but smell later). Or is this something I have to live with that they "do it" a little when cold?

Again maybe many of you don't have this because you go straight out from your stove thru the wall but obviously those going through the roof will have one 90 and in my case to 45.

What kind of cap are you using, as you may know pellet stoves are a class5 vent type so They are mechanically assisted usually resulting in creating a good draft. Looks like your getting poor "draft" too. Also are you using L vent?
 
OK...now we are getting somewhere!

That is good intel. If a little smoke for a minute or two is to be expected and my efforts to seal and tape will work once it gets warm and expends I'm sure I'll be good. Got a little hotter then I liked tonight so the chemical smell from the caulk was strong. Hoping I didn't do any damage to it!

Will report back tomorrow when we fire this up for a few hours!

PS. My stove doesn't require cold air intake (only for trailers) so we didn't do it (yet). I get what appears to be a great draft in my current setup but will getting that fresh air intake hooked up improve the woody smell at all...or not likey?
 
What kind of cap are you using, as you may know pellet stoves are a class5 vent type so They are mechanically assisted usually resulting in creating a good draft. Looks like your getting poor "draft" too. Also are you using L vent?

It's a duravent cap...I can take a photo, right angle. Seems like the draft is pretty good to me. It pulls hard in the chamber and pumps it out at the cap well enough. It's a right angle where it exits. I've included a photo...

Don't judge on the angle of the exit pipe. We need to get another block off wood under the part that holds the pipe to the wall. Waiting for the weather to break to get out there and straiten the angle to get it off the wall...as it's only about 3-4 inches off the wall and crooked.

I've got 2.0ft of pipe inside (with two 45) and 3.5ft of pipe outside with a 90 out there.
 

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Getting to vauge for the new guy here.

Evl?
Are we talking Elevation...then 1000ft in Ohio. Nothing to concerning.
Sorry. Your manual should have a conversion table for you pipe runs. I believe the limit on 3 Inch pipe is 15ft if remember correctly and I also believe 90, s and tees are 5ft a piece if thats what your manual says your maxed out and need 4inch pipe. But check your manual forthose specs
 
Exhaust vent length.
 
My stove install was 5ft for the clean out tee and 15 ft of straight pipe equaled 7.5 so total it was 12.5 ft just under the 15ft allotted
 
There should be another 90 at the top of the pipe outside before the cap. The cap should face down or else you will get water in it when it rains.

You might also want to consider an adjustable bracket for the pipe so you don't have to use the blocks of wood. Because I needed to use a two foot section through the wall so no joint was inside the thimble my pipe is a good distance from the house. See the picture below how I extended the adjustable bracket using some pieces of aluminum. I think it looks better and you can cut it to exactly the length you need.

[Hearth.com] help with leaks and smell...
 
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Sorry. Your manual should have a conversion table for you pipe runs. I believe the limit on 3 Inch pipe is 15ft if remember correctly and I also believe 90, s and tees are 5ft a piece if thats what your manual says your maxed out and need 4inch pipe. But check your manual forthose specs

In right at 15. Again draft seems good. The issue is smoke at the seams. How does draft impact that? Slow equals smell and smoke? Also, if my outlet is 3" hoe can I use 4". Simply an adapter eould suffice? Seems that would slow draft more!

Are we staying on topic or just receiting tech specs that may have no merit if I'm justvtryingvto seal seems

Thanks.

That chart is useful and compares to what the manual says. Evan at 2000ft I'm good for 20ft and I"m only doing about 16-17ft (erroring on long) including angles and I have the 3ft minimum required outside. I should be good...just need to solve these interior leaks!
 
I believe what where doing here. Is called making up for the lack of information you gave us! I didnt read anywhere about politics or sports so yes we are staying on topic! Do you want insight and help or no? Us trying to gather info is not going off topic so grab a beer and relax dude.
 
With Duravent, I find that I need to silicone the inside and outside of every seam I won't need to take apart for cleaning - including the factory seals of the 45's - and then to wrap the outside of seams I need to take apart for cleaning with high temp silicone tape - 3M is great - as well. Perhaps a lack of sealing those factory seals that you would think are fine is the problem? It looks ugly but can be painted over with high temp stove paint once the problem is resolved, which helps significantly. Using a flashlight in a dark room AT STARTUP - before stove has significant force and draft - is the best way to find leaks.

Now, all that said, let be be blunt here: Don't snipe back at people who are trying to help you. Considering EVL is a very appropriate item in this discussion, and not knowing what it is tells us you don't know beans about a pellet stove. We've all been there, and people are generally very happy to help, but your comment about "tech specs" shows a lack of appropriate patience for solving what can be a problem for many experienced owners. People here are happy to help, but if you display attitude at 9 posts in, with all of it being in a thread where people are working for free on your behalf, people are likely to not give a hoot about your smoke problem. Take that for what it's worth.
 
In right at 15. Again draft seems good. The issue is smoke at the seams. How does draft impact that? Slow equals smell and smoke? Also, if my outlet is 3" hoe can I use 4". Simply an adapter eould suffice? Seems that would slow draft more!

Are we staying on topic or just receiting tech specs that may have no merit if I'm justvtryingvto seal seems

Thanks.


That chart is useful and compares to what the manual says. Evan at 2000ft I'm good for 20ft and I"m only doing about 16-17ft (erroring on long) including angles and I have the 3ft minimum required outside. I should be good...just need to solve these interior leaks!
Are you possibly trying to vent into a prevailing wind?
 
Instead of foil tape have you tried self bonding silicone tape? It stretches very tight and seals very well. No wrinkles to leak.
 
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Secret trick.

Get the stove going, turn off the lights (Dark room)
Use a laser pen and go around the stove and vent carefully, any wisps of smoke will show up REAL WELL in the red laser.

Check the connection to the stove and all the joints.

Any sealing must be done with 500 F rated silicone (Black is common)

Do not use other caulks.

The high temp foil tape is great for wrapping the joints and seals well.

Did you silicone the joint to the stove ??

Once the stove is running, the intake from the room air fan will spread the smoke smell everywhere, do a visual in the dark with the light is the best way to search out the source.

Is this a new stove ??

If not, then a good snooping is in order to source and stop any leaks.

Good luck, and keep us posted.

Snowy
 
More vent equals more draft equals less backpressure equals less smoke. If you can't seal the seams with tape you may have another problem; too little draft, too much backpressure. Your stove, like Lassie, may be trying to tell you something.
 
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I had the same problem, The solution was to clean the pipe with alcohol nothing will stick to the fly ash after it gets on the pipe, then wrap the elbows with silicone tape.
I purchased the tape at a local big box store in the electrical department.
 

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