sealing vent pipe

[gog222]

I have a question concerning Pellet Stove venting. Should you use a sealant around the seams of you pipe? I have heard yes and no..any comments? I wouldn't think it would hurt if you did.

 

[rap69ri]

You should definitely seal the joints on the inside of the house at the very least with high-temp RTV, and 3 screws if not using the Simpson Duravent that twist locks.

 

[djarseneault]

It depends on what brand pipe you are using. Simpson Pro-Vent and Excel pellet vent don't need sealant from pipe to pipe, only from the stove to the first pipe. For the pipe that needs sealing, use 500deg clear silicone and apply to the joints after you assemble them (makes it easier to take apart if you need to later). Don't need to bother sealing the pipe that is outside the house though

 

[zionadams]

We installed new Simpson Duravent two days ago, without sealing it...I wish I'd know that information at the time.
You'd think they'd put it on a label or something. Darn! We've not had any leaking (visible) with the new pipe. Still, my husband asked the same question.

 

[bostonbaked]

I spoke with a Technician at Dura Vent recently and asked him that question. His answer was to only seal the inner pipe with a bead of sealant where the two pieces over lap. He also said sealing the outer pipe joints is not the way they recommend. He said if the inner pipe is sealed correctly that's all that's needed. He went on to explain that the outer pipes purpose is to draw fresh air through to keep the pipe cool, He also said when installing the stove with an appliance adapter to never seal any part of the pipe other than where it slips over the stove outlet. He said if you do so you will negate the purpose of the outer pipe. He told me that if I were to be getting leakage at the joints the failure is on the inner pipe joint. Only fresh air is supposed to be in the outer pipe. He said putting a bunch of sealant of the outer pipe joints is only an attempt to solve the problem that lies within the inner pipe. This is direct from Dura Vent. If you check their site they have a diagram that shows where to put the bead of sealant.

 

[JML1]

After you use the silicone sealant how long should you wait before using the stove.

 

[djarseneault]

I spoke with a Technician at Dura Vent recently and asked him that question. His answer was to only seal the inner pipe with a bead of sealant where the two pieces over lap. He also said sealing the outer pipe joints is not the way they recommend. He said if the inner pipe is sealed correctly that's all that's needed. He went on to explain that the outer pipes purpose is to draw fresh air through to keep the pipe cool, He also said when installing the stove with an appliance adapter to never seal any part of the pipe other than where it slips over the stove outlet. He said if you do so you will negate the purpose of the outer pipe. He told me that if I were to be getting leakage at the joints the failure is on the inner pipe joint. Only fresh air is supposed to be in the outer pipe. He said putting a bunch of sealant of the outer pipe joints is only an attempt to solve the problem that lies within the inner pipe. This is direct from Dura Vent. If you check their site they have a diagram that shows where to put the bead of sealant.

The problem with the so called technicians at the factories is they have little to no real world experience. Sealing the outer pipe has no effect on the air space in between the two pipes. That air space has no actual air flow, so sealing it will not affect it as far as safety goes.
The practical problem with sealing the inner pipe is that you can forget about separating the pipe once it is sealed. In some instalations you need to be able to disconnect the pipe to do a full cleaning. And what do you do when you have sealed the inner pipe, put it all together, and it leaks? Do you take it all apart and try again?
Not trying to be a pain here, just trying to share my experience.

 

[djarseneault]

After you use the silicone sealant how long should you wait before using the stove.

As soon as it "skins over"

 

[JML1]

thanks Parrot head

 

[richg]

I spoke with a Technician at Dura Vent recently and asked him that question. His answer was to only seal the inner pipe with a bead of sealant where the two pieces over lap. He also said sealing the outer pipe joints is not the way they recommend. He said if the inner pipe is sealed correctly that's all that's needed. He went on to explain that the outer pipes purpose is to draw fresh air through to keep the pipe cool, He also said when installing the stove with an appliance adapter to never seal any part of the pipe other than where it slips over the stove outlet. He said if you do so you will negate the purpose of the outer pipe. He told me that if I were to be getting leakage at the joints the failure is on the inner pipe joint. Only fresh air is supposed to be in the outer pipe. He said putting a bunch of sealant of the outer pipe joints is only an attempt to solve the problem that lies within the inner pipe. This is direct from Dura Vent. If you check their site they have a diagram that shows where to put the bead of sealant.

Oh, those people need to get a clue. Simpson whore a vent leaks six ways to Sunday due to its poor design and Fischer Price construction. Your best bet: assemble your piping, and then seal every seem joint rivet crimp bend notch gap turn etc you can find with rtv. Then, and only then, can you be sure that their crap product won't leak. If I did my job as poorly as they do theirs, I'd have been fired and sued years ago.

 

[StoveMiser]

I have to say I have been very pleased with duravent. I have never sealed the joints and have never had a problem with leakage. Never really understood why people would seal it. All of my joints are extreme tight when I twisted them together. The only way I could see it leaking is if the vent was plugged. Stands to reason the combustion exhaust is going to find the easiest path. Can't see those tight seams being the easiest path...

Maybe I have just been lucky, but that's just not the way my life works. Lol

 

[imacman]

I have to say I have been very pleased with duravent. I have never sealed the joints and have never had a problem with leakage.....

I agree Miser. I did my own install, and the only place I used Hi-Temp silicone is where Simpson said to use it....on the appliance adapter. Otherwise, I was told not to seal anything else by the local stove shop.

Have not had a single leak anywhere in the piping. Put the stove on High fan, and ran lit matches around all the joints looking for a flicker....nothing. I have CO detectors all through the house.....not a peep out of them.

 

[woodsman23]

I have to say I have been very pleased with duravent. I have never sealed the joints and have never had a problem with leakage.....

I agree Miser. I did my own install, and the only place I used Hi-Temp silicone is where Simpson said to use it....on the appliance adapter. Otherwise, I was told not to seal anything else by the local stove shop.

Have not had a single leak anywhere in the piping. Put the stove on High fan, and ran lit matches around all the joints looking for a flicker....nothing. I have CO detectors all through the house.....not a peep out of them.

I simply placed metal tape around all joints and nothing seals better than this stuff.

 

[staplebox]

I initially sealed the inner joints and still had a leak. I tried adding rtv to the outside of the joints (including the outer bend if the 45, piece of crap) and still had a leak, and it looked like crap. I eventually ended up using high temp silicone tape. You can find if in the plumbing section. I wrapped it around every joint and the 45. Works great , holds fast, doesn't melt, easy to apply and actually looks nice.

 

[djarseneault]

The new "pro-vent pipe" does not need to be sealed. The standard one does, and also the "pro-vent" that was produced before they got smart and started using silicone gaskets in the joints. Simpson had to step up the quality because their domination of the pellet vent market would have taken a major hit when ICC Chimney introduced their Excel pellet vent.

 

[slink]

After you use the silicone sealant how long should you wait before using the stove.

We install and fire the stove for the customer with in minutes of the last joint being sealed. Never had an issue with the silicone. An advantage is "if" there is a leak you can still remove the pipe and reseal before the silicone sets up.

 

[imacman]

After you use the silicone sealant how long should you wait before using the stove.

We install and fire the stove for the customer with in minutes of the last joint being sealed. Never had an issue with the silicone. An advantage is "if" there is a leak you can still remove the pipe and reseal before the silicone sets up.

I agree...I fired my stove within 1 hour of assembly and I used sealant on appliance adapter. Didn't have any problems.

And slink has a good point about being able to take it back apart if there IS a problem.

 

[MainePellethead]

I used ICC pipe with silicone gaskets...no sealant at all.....love it!

 

[bostonbaked]

I spoke with a Technician at Dura Vent recently and asked him that question. His answer was to only seal the inner pipe with a bead of sealant where the two pieces over lap. He also said sealing the outer pipe joints is not the way they recommend. He said if the inner pipe is sealed correctly that's all that's needed. He went on to explain that the outer pipes purpose is to draw fresh air through to keep the pipe cool, He also said when installing the stove with an appliance adapter to never seal any part of the pipe other than where it slips over the stove outlet. He said if you do so you will negate the purpose of the outer pipe. He told me that if I were to be getting leakage at the joints the failure is on the inner pipe joint. Only fresh air is supposed to be in the outer pipe. He said putting a bunch of sealant of the outer pipe joints is only an attempt to solve the problem that lies within the inner pipe. This is direct from Dura Vent. If you check their site they have a diagram that shows where to put the bead of sealant.

Oh, those people need to get a clue. Simpson whore a vent leaks six ways to Sunday due to its poor design and Fischer Price construction. Your best bet: assemble your piping, and then seal every seem joint rivet crimp bend notch gap turn etc you can find with rtv. Then, and only then, can you be sure that their crap product won't leak. If I did my job as poorly as they do theirs, I'd have been fired and sued years ago.

If you bought that cheap crap at Home Depot I agree. The pro pipe is welded no rivets to speak of . You can leave a section unsealed out side to gain access for cleaning. How anyone can make a blanket statement as to what some tech. has in his or her home is a mystery to me. He or she (may) have far more experience burning than you or I. It's just your opinion.( actually Parrotheads sorry ) There is no way to know that. Don't shoot the messenger. You obliviously bought their crappy pipe so what makes you an authority ?

 

[bostonbaked]

Just to clarify what the tech. said about sealing the outer pipe. The conversation was about how the appliance adapter has the inner pipe that extends beyond the outer pipe by about a half inch to allow it to be screwed to the stove outlet. He said some people have been known to try filling the gag between the inner and outer pipe with sealant. Why. I do not know but that is what I meant about negating the purpose of the outer pipe. And he did say that that gap is there to allow air to be drawn through. Just wanted to clear up any confusion. And I think everything he said made perfect sense, to me at least.

 

[Alan]

I initially sealed the inner joints and still had a leak. I tried adding rtv to the outside of the joints (including the outer bend if the 45, piece of crap) and still had a leak, and it looked like crap. I eventually ended up using high temp silicone tape. You can find if in the plumbing section. I wrapped it around every joint and the 45. Works great , holds fast, doesn't melt, easy to apply and actually looks nice.

Can you point the a URL for the exact tape you are using? Did you get it at a chain store?

There seem to be so many type, different backings, etc. Also you said it was in the pluming section -- I've seem some from an internet search that are for the electronics industry.

Thanks, Alan

 

[woodsman23]

I initially sealed the inner joints and still had a leak. I tried adding rtv to the outside of the joints (including the outer bend if the 45, piece of crap) and still had a leak, and it looked like crap. I eventually ended up using high temp silicone tape. You can find if in the plumbing section. I wrapped it around every joint and the 45. Works great , holds fast, doesn't melt, easy to apply and actually looks nice.

Can you point the a URL for the exact tape you are using? Did you get it at a chain store?

There seem to be so many type, different backings, etc. Also you said it was in the pluming section -- I've seem some from an internet search that are for the electronics industry.

Thanks, Alan

www.aviationsiliconetape.com

 

[staplebox]

I initially sealed the inner joints and still had a leak. I tried adding rtv to the outside of the joints (including the outer bend if the 45, piece of crap) and still had a leak, and it looked like crap. I eventually ended up using high temp silicone tape. You can find if in the plumbing section. I wrapped it around every joint and the 45. Works great , holds fast, doesn't melt, easy to apply and actually looks nice.

Can you point the a URL for the exact tape you are using? Did you get it at a chain store?

There seem to be so many type, different backings, etc. Also you said it was in the pluming section -- I've seem some from an internet search that are for the electronics industry.

Thanks, Alan

Sorry, can't find a link for you. There used to be a picture posted here but I can't find it. I got the tape at Home Depot. It was with the plumbing stuff like teflon tape, pipe dope, etc. It was about $5 for a roll that was all I needed. 500 degrees. It is a milky white color. Hope that helps.

 

[pellet0708]

OK help me out. I did put some silcone around that gap between the outer wall and inner wall near the appliance adapter. Have icc excel. I know is overkill but on the off chance there was a leak in the inner wall I figured we were covered. I can't believe there is supposed to be any airflow in that outer wall. Just there for insulation value. If there was supposed to be airflow it would be marketed like the selkirk is.

Am I right??

 

[bostonbaked]

If your asking me, I can't tell you. I asked him about the pipe and these are some of the things he stated I was looking for info. like the OP He convinced me he knew his product. I don't know for sure, but, I would think with the inner pipe as hot as it gets would stay cooler if a free flow of air can enter and exit the outer pipe. His point was not to interrupt the flow. He said use sealant only on the stove outlet. I believe that makes sense. You can do as you like. We don't have to agree, just sharing what the people who made the pipe told me.