clear rtv hi temp silicone?

[kgreene]

Can someone recommend a brand and place to get clear (not red) hi temp rtv silicone sealant for sealing pelletvent duravent venting? I would like to get a caulking tube rather than a smaller hand tube. All the local places I have called seem to only carry red and don't seem to know about clear though people here have talked about it.

Does the temperature really matter? That is, 500 vs 600 or whatever, obviously you'd need a minimum.

This is for a retrofit BTW, we moved into a house with an old thompson-thelin pellet stove (1987 vintage) and I realized (after smelling vent gases easily when using it) that the original owners had used B type gas venting with no sealant! I'm not sure they had ever cleaned out the manifold after I opened up the cleanout and 3-4+ cups of ash just fell out!

After reading a lot on this forum I've decided to use the old original "multiple 90-degree turns, 1 foot rise (with vertical cap), horizontal out then up venting" holes to put in ducting for outside air since the hole is already there.

Any help is appreciated.

thanks,

Kevin

 

[Wet1]

I've never seen clear hi temp. The only hi temp I've seen is the orange. I believe the Ultra Copper is rated pretty high as well, but it's not clear either.

 

[slls]

Stove stores have black hi-temp in caulk tube size, not sure about clear.

 

[sammypoodle]

I picked up some Rutland Clear 500 degree temperature silicone caulk clear for $5.95 (usa) at Home Depot.

 

[moralleper]

I picked up tube for a caulking gun, Clear Rutland 500 degree at Ace hardware for 6.95.

 

[wilbilt]

Clear Rutland Hi-Temp at Tractor Supply here.

 

[hossthehermit]

I like the red stuff, wife thinks it's pretty. Seriously, you want to tape the joints, as well, IMHO, so who's gonna know what color the silicone is?

 

[kgreene]

I like the red stuff, wife thinks it's pretty. Seriously, you want to tape the joints, as well, IMHO, so who's gonna know what color the silicone is?

So you need to caulk the outside and then tape also? Can you use standard metal duct tape or is there a special high temp kind? Do you wait for the silicone to set before applying the tape?

 

[Xena]

I realized (after smelling vent gases easily when using it) that the original owners had used B type gas venting with no sealant!
After reading a lot on this forum I've decided to use the old original "multiple 90-degree turns, 1 foot rise (with vertical cap), horizontal out then up venting" holes to put in ducting for outside air since the hole is already there.

Not clear on what you're saying exactly, but hoping you
are going to remove that B gas vent and replace it with
pellet vent. Just sealing the vent rated for a gas appliance
is not the right thing to do.

 

[jtcm05]

I picked up some Rutland Clear 500 degree temperature silicone caulk clear for $5.95 (usa) at Home Depot.

Same here...

 

[firewarrior820]

[/quote]

Not clear on what you're saying exactly, but hoping you
are going to remove that B gas vent and replace it with
pellet vent. Just sealing the vent rated for a gas appliance
is not the right thing to do.[/quote

you need to reread kgreen post, he's not using gas vent piping

 

[Xena]

you need to reread kgreen post, he's not using gas vent piping

I read it again and I still find the post confusing particularly where
he says this:
I realized (after smelling vent gases easily when using it)
that the original owners had used B type gas venting with no sealant!

Apparently he's removed the B vent that the original owners
had installed and he replaced with simpson duravent but that wasn't
too clear the way the post was written.

 

[smilejamaica]

home depot has clear . thats the place i got mine . also this company has it for sale http://www.grainger.com/Grainger/items/1FBJ1

 

[kgreene]

Yes, I have removed the old B type venting. I will use the holes for the old venting to run outside air combustion venting. I am drilling new holes to install the pellet vent.

Do most people rtv caulk then tape (what type of tape?) each seal? I talked with a local installer who recommended sealing each joint externally with rtv only, except for the connection to the stove itself which he recommended applying rtv inside as well as actually drilling screw holes and screwing the pipe to the stove itself to prevent that seal breaking.

It's strange, I have looked locally at several hardware stores and stove retailers...I can find red rtv and some high temp clear that is NOT rtv (I thought I needed to use rtv though?) which I think was rated at 450 degrees. I ended up returning that because it was below the temp rating specified (500).

thanks,
kevin

 

[Xena]

I used Permatex Ultra Copper high temp rtv on the inside
of my Simpson Duravent, and three screws on the outside -
I did not use rtv on the outside. No leaks here.
We put my stove in Nov 2005 so my Duravent
is the older stuff. I heard the new Simpson Duravent is made better?