Stove & Gasket Cement or RTV Sealant???

[DV]

The guy at my local ACE hardware today recommended I use " Rutland Hi Temp Stove & Gasket Cement" instead of the hi temp red RTV sealant on my pellet vent pipe. I'm having some issues with leaking joints on my 4 " Duravent pro piping and trying to get a good seal. This stuff is black and comes in a caulk tube. Has anyone used this? And would you recommend this over the RTV sealant?

 

[SmokeyTheBear]

Rutland has several products that come in tubes and are black. What does the tube say to use it for and what is the actual temperature rating?

Some cements are just that and don't act as a true sealant. For example the gasket is held in place by a small amount of cement but the actual seal is the compressed gasket material.

You need a high temperature sealant, your mechanical fastening system is the small self taping metal screws.

 

[P38X2]

I wouldn't use it. If its the same stuff I'm thinking about, the plumbers used it to seal the vent pipe on my DV Buderus boiler. Over time it cracked and leaked. I believe it was because the quantity used was too little and due to the repeated expansion and contraction of the pipe, the cement cracked. It was applied in the same quantity as a silicone based product would have been. Ultimately, I chipped out as much as I could and re-sealed it with RTV. Problem solved. IME, gasket cement is the wrong product to use on a vent pipe.

I had a similar issue as yours with DV Pro. I taped and taped and still had the problem. Its just too hard to get tape to lay completely flat on a curved surface and small ripples, aka pinhole leaks, will remain. I ended up having to remove all the tape, which SUCKED, and went with high temp silicone, the clear stuff. I sealed EVERY point there was. Every connection joint, swivel point, rivet and went as far as sealing the crimp seams that ran along the lengths of the pipe sections. It was kind of a pain but it can be done neatly. At the stove connection, I taped that as neatly as possible with 2-3 layers placed exactly over each other. I then sealed the edges of the tape with silicone. I did the same with each joint connection, using only a single layer of tape. Problem solved.

I think a lot of people use tape, sometimes successfully, to SEAL and secure pipe sections. IME, securing yes, but sealing doesn't always work, especially on articulating sections. It seems the bad reputation DV Pro gets are well earned.

 

[DV]

Here is a pic. 2000 f is the rating. Would this be better than the RTV sealant?

 

[P38X2]

I believe that is the same product as what's found in the small tubs.

 

[SmokeyTheBear]

Wrong stuff.

ETA: Rutland makes a 800 black silicone sealant called seal it right which is a sealant not a cement.

If there is already stuff on the joints you need to use the same thing or risk possible non binding or worse softening or loosening of what is already there.

 

[P38X2]

Somewhere on the shelf, very close to where that product was, should be the Rutland high temp silicone. That's what you want.

 

[P38X2]

This stuff. It worked for me and hasnt deteriorated. On my second stove, the installers used a black silicone which was likely what Smokey is talking about. Higher heat resistance = more peace of mind.

 

[DV]

Thanks! I have a tube of red 500f RTV automotive sealant that I have used before. I guess my best option would be to seal every gap/screw/seam and invisible pinhole I can find and then tape the hell out of everything. Should I use the automotive sealant I already have or would you recommend the Rutland silicone??

 

[P38X2]

Not exactly sure but I'd assume the automotive RTV would work fine. That's what's on my boiler vent. Check the heat rating on it. I believe the red/orange stuff is 500F at least.

 

[greg13]

I would go with the high temp. Silicone. If you ever have to remove it The cement would be a major pain to get apart.

 

[P38X2]

DV, how goes the battle?

If you haven't done it yet, one downside to using red RTV is it's red. If you're not gonna see any of the pipe then obviously its not a problem. If you can then you may end up having to paint the pipe with high temp paint which is gonna be another $10 or so. Depending on your installation, you'll likely have to use the brush on paint as opposed to the spray can.

 

[DV]

DV, how goes the battle?

If you haven't done it yet, one downside to using red RTV is it's red. If you're not gonna see any of the pipe then obviously its not a problem. If you can then you may end up having to paint the pipe with high temp paint which is gonna be another $10 or so. Depending on your installation, you'll likely have to use the brush on paint as opposed to the spray can.

Got the red silicone on everything last night. I even sealed up the secondary annular space at the stove adaptor. Gonna let it dry for the day and this afternoon tape everything then fire the stove up and cross my fingers. I will paint the pipe eventually once I get the leaks resolved. Thanks for the advice.

 

[DV]

Got the red silicone on everything last night. I even sealed up the secondary annular space at the stove adaptor. Gonna let it dry for the day and this afternoon tape everything then fire the stove up and cross my fingers. I will paint the pipe eventually once I get the leaks resolved. Thanks for the advice.

Heres the deal. In my opinion I think I'm good. It doesnt smell at all to me. Had the stove running for about an hour with no issues. The real test was the wife. She didnt say a word and didnt know it was running. Then I took the dog out for a walk and could smell the stove exhaust outside. I went over and checked on the exterior exhaust and eveything was good. So then I come back inside with smoke on me and the door open and the wife comes downstairs and says she still smells it. So I try to explain to her the stove has been on and she probally smells the smoke from me being outside. Of course she says no way and that it still smells. So I'm letting the stove run for a while and we will see. Man its always something. She will also be the first to complain when she is cold. Oh well I'm having a drink. Cheers.

 

[P38X2]

Heres the deal. In my opinion I think I'm good. It doesnt smell at all to me. Had the stove running for about an hour with no issues. The real test was the wife. She didnt say a word and didnt know it was running. Then I took the dog out for a walk and could smell the stove exhaust outside. I went over and checked on the exterior exhaust and eveything was good. So then I come back inside with smoke on me and the door open and the wife comes downstairs and says she still smells it. So I try to explain to her the stove has been on and she probally smells the smoke from me being outside. Of course she says no way and that it still smells. So I'm letting the stove run for a while and we will see. Man its always something. She will also be the first to complain when she is cold. Oh well I'm having a drink. Cheers.

Lol, yeah they seem to have an uncanny ability to detect foreign odors and jump to conclusions. Don't ever go to a perfume store to find her the newest sexy stuff if you don't plan on giving it to her immediately upon walking through the door. You'll be sorry.

Glad your issue seems to be solved. That pellet smoke is pungent for sure. Cheers.

 

[SmokeyTheBear]

You need to stay away from the exhaust when outside.

 

[DV]

You need to stay away from the exhaust when outside.

Ten four on that. Should be all set on the sealing. I sealed everything I could see that was a seam. This morning I did not smell smoke in house. Another question is how do you guys fasten the stove adaptor to the stove? Orignally I used a 4 inch hose clamp and RTV sealant inside of fitting. But I took off the hose clamp to caulk all the external seams and seal up the secondary at the t adaptor. I did not put the hose clamp back on and the T appears to be on very solid. I could not remove it by hand. I could put the hose clamp back on but I'm worried about putting different pressures on my fresh seal and then having a leak again. Any advice?

 

[SmokeyTheBear]

Ten four on that. Should be all set on the sealing. I sealed everything I could see that was a seam. This morning I did not smell smoke in house. Another question is how do you guys fasten the stove adaptor to the stove? Orignally I used a 4 inch hose clamp and RTV sealant inside of fitting. But I took off the hose clamp to caulk all the external seams and seal up the secondary at the t adaptor. I did not put the hose clamp back on and the T appears to be on very solid. I could not remove it by hand. I could put the hose clamp back on but I'm worried about putting different pressures on my fresh seal and then having a leak again. Any advice?

You are supposed to mechanically fasten that adapter to the stove, the normal method is a self taping screw.

 

[P38X2]

You are supposed to mechanically fasten that adapter to the stove, the normal method is a self taping screw.

+1
I'd carefully use just tape on the T cleanout cuz there's not really any other option.

 

[DV]

Thanks. Dont want that thing popping off. Probabilty is low but i will sleep better with 2 screws in it.