Can't seal leak at the collar... what's going on?

[DIYstoveGUY]

I'm sure there will be many questions about my setup but he's what I can say. I have a VC montpelier in a exterior chimney with a 6in stainless liner about 18ft. At the insert I have a quick connect style adapter ( stainless steel appliance adapter) going from the liner into the collar. Yes it's screwed in through the holes in the collar.

I can not keep this thing from leaking for the life of me. I've used furnace cement and that stove and fireplace cement&mortar black paste stuff.

Every now and then I notice the insert really isn't getting up to temp and not good secondaries. So I pull the surround and anything that I've put around the connection to the collar for sealing up little leaks that I've found with a lighter, it always leaking again.

I've let the stove completely cool down. Clean off everything that was on the joint with a wire brush I've tried sealing it with 2 different things mentioned above and let them dry over night before I slowly brought the stove back up to temp. What am I doing wrong? It's the end of the season so I'll be pulling the stove this summer to make block off plate and I'll be starting fresh with a new connection that I got from Rockford but other than that I don't know what else I can do.

Sorry if I'm a little all over the place just trying to put everything down before I forget something I wanted to include in the post. Any input would be appreciated... thanks guys

 

[bholler]

I'm sure there will be many questions about my setup but he's what I can say. I have a VC montpelier in a exterior chimney with a 6in stainless liner about 18ft. At the insert I have a quick connect style adapter ( stainless steel appliance adapter) going from the liner into the collar. Yes it's screwed in through the holes in the collar.

I can not keep this thing from leaking for the life of me. I've used furnace cement and that stove and fireplace cement&mortar black paste stuff.

Every now and then I notice the insert really isn't getting up to temp and not good secondaries. So I pull the surround and anything that I've put around the connection to the collar for sealing up little leaks that I've found with a lighter, it always leaking again.

I've let the stove completely cool down. Clean off everything that was on the joint with a wire brush I've tried sealing it with 2 different things mentioned above and let them dry over night before I slowly brought the stove back up to temp. What am I doing wrong? It's the end of the season so I'll be pulling the stove this summer to make block off plate and I'll be starting fresh with a new connection that I got from Rockford but other than that I don't know what else I can do.

Sorry if I'm a little all over the place just trying to put everything down before I forget something I wanted to include in the post. Any input would be appreciated... thanks guys

You need to use gasket to seal it

 

[webby3650]

I don’t think this small leak would be causing poor performance, unless it a big gap, typically no sealant is used there. Does yours have an unusually big gap?

 

[DIYstoveGUY]

It really does make a difference when it's sealed. The stove struggles to hit 400 when it's leaking with poor secondaries. When it's all sealed up, I get a steady 500 at the top of the door arch and nice longer secondaries.

It's a 6inch collar and liner and even with it screwed into the collar, I'd say it has almost 1/16 heavy gap. Someone suggested flat gasket to sealit better

 

[webby3650]

With a 1/16” gap, flat gasket is about your only option.