Sealing the liner conector to the stove

[wg_bent]

Here is a picture of the chimney liner stove side connector sitting on top of the Osburn. How do you seal the connector to the stove?

I'm thinking of getting a short peice that fits into the stove on one side and outside the connctor on the other. and sealing the joints with some ceramic rope. Seam (spelling mistake and pun intended) reasonable?

Warren

 

[saichele]

Seems plausible. If it's accessible, I'd even consider just working a little stove cement in there. There's some magic silicone MO keeps talking about that might work (BOSS somthing), but it doesn't have to be a great seal.

If you wanted to get fancy, get some of the stove gasket tape ($8 at TrueValue) with the sticky back, and just run a bead all the way around inside the collar. The adhesive may fry, but by then the pipe will be holding it in place.

Steve

 

[Willhound]

Holy crack! Is the outlet on the insert that out of round? Or is the liner attachment bent? I've seen some slight gaps in pipes I've installed over the years, but never anything like that.

Willhound

 

[wg_bent]

That's the difference in size created by the liner coupling and the stove outlets inside diameter. You can see the coupling is fluted (correct term?) The coupling may be slightly out of round, but the gap is due mostly to differnence in size and that it can't be pushed into the stove.

Warren

 

[Willhound]

When you say "it can't be pushed into the stove", are you saying that it can't be shoved any further into the hole? How much of the fluted section is still sticking up? Is there a piece of weld splatter or something down in the hole that is holding you up?

Most of my experience over the years has been with free standing wood stoves of which I've installed about half a dozen, and probabley helped friends with about the same number, so I'm no expert, but I can share that there have been instances where I've had difficutly getting the connector pipe down far enough into the stove to the point where we had to get pretty creative, i.e. beating them in (carefully) by placing a piece of soft lumber evenly across the pipe and giving it a few good wacks. Of course, you need to be careful not to bend the edges of the connector pipe too much. I've also seen us put the connector pipe in the freezer for a few hours and at the same time heat the neck of the stove up to expand it slightly. Doesn't sound like it would make a big difference, but it can work. Once, with a particularly tight pipe, we had to resort to adding a few crimps of our own, and then beating these back out from the inside once the pipe was in, but not reccommended.
I only make these suggestions because if your connector pipe isn't seating far enough down into the insert, my opinion is that you risk not getting a good seal regardless of what type of flashing or cement you try and put around it.

Maybe some of the more experienced "insert" guys can wiegh in here?

Willhound

Oh, one last thing. There was also once where we took the connector we had back to the hardware store and got another one to try. The new one fit perfect....it seems that the pipe manufacturer's specs were out that much.

 

[thechimneysweep]

You don't want to use door or glass gasket to make this seal: the flue collar is right above the secondary burn chamber, and the hi-temp fiberglass won't hold up at that temperature.

Go to your local hardware store, hearth product shop or home improvement center and get a caulk tube of furnace cement. Lay a bead so it fills the gap between the flue collar and the crimped end of your connector, then let it cure at room temperature for a few hours before having a fire. Furnace cement goes on like peanut butter and hardens like rock, and will make a permanent seal.

 

[elkimmeg]

here is another suggestiom crimpimg is usually 1.5" then a flat area and a rib what I have had to do is measure down t the length of thr collar and cut the bottom of the crimping. I measure down from the rid and cut off the excess length the final fitting will be at the rib it fills most gaps and if furnace cement is needed I apply a beed. The stuff Mo is talking about is BOSS 136 Firestop Draft Sealant
Meets ASTME E 814 & E 136 standard the 136 is the standard others Caulk manufactures meet Rutland Dap and others.
It may be used for this purpose Tested to 3000 degrees www.accumetricinc.com listed for wood stove applications

DAP ASTM E 136 Rated Fire resistant motar Rated to 2000 degrees listed to be used to patch wood stoves
www.dap.com/

"Noncombustible/ASTM-E136 fireblocking sealants are made of inorganic materials such as minerals and silicates that cure hard like a mortar or cement. Due to the intense heat requirements of the ASTM-E136 test, organic materials ignite and exhibit products of combustion.

Materials that pass the ASTM-E136 standard of noncombustibility are tested to withstand in excess of 1380° F demonstrating that it will have a greater burn time/ temperature than wood. In addition, the mineral composition allows noncombustible sealants to be unaffected by age, remaining effective as a fireblock for the lifetime of the structure."