Block off plate and Liner Hole size

[Jambx]

I just made my block off plate for my damper area however I have not made the hole in which the liner has to pass – I was wondering;

1) I assume the hole / location be made before or after the liner is in?..
2) When the hole is made is there a preference as to the size of the hole to either accommodate the liner insulation (6.5+ inches) or just big enough for just the stainless liner (6 inches) does it matter?..

Any feedback would be greatly appreciated,

~jim

 

[Milton Findley]

Before was my choice, and I did not run the insulation down past the block off plate. I made the hole 6 and a quarter inches, and I put insulation around it after the liner was through it. The liner was coming straight down at that point, and it fed through without difficulty. If I had it to do over again, I would consider running the insulation all the way down to the Tee connector.

 

[begreen]

This may depend on the angle of the smoke chamber and damper box. When in doubt I would wait for the liner and template with cardboard, especially if the hole needs to be slightly oval to accommodate the liner angle.

 

[Milton Findley]

This may depend on the angle of the smoke chamber and damper box. When in doubt I would wait for the liner and template with cardboard, especially if the hole needs to be slightly oval to accommodate the liner angle.

Yeah, that too :red: I cut the hole while I was still of the belief that flex liner was flexible.

If I had it to do over again, I would have left the block plate, (which was my old damper plate), off entirely and stuffed unfaced rock wool into the chimney pipe to block air flow up the former air cooled chimney after I got everything measured and cut. (The lost heat from not installing the plate is lost inside my living space, so it is not lost after all but I did not know that at the time). If I ever have to reline, it will be a 3 hour job.

 

[Stax]

I'm at the same stage Jambx. I'm waiting for my liner. Once I get it, tracing a simple circle around it on the block off plate and Kaowool board.

 

[Jags]

I'm at the same stage Jambx. I'm waiting for my liner. Once I get it, tracing a simple circle around it on the block off plate and Kaowool board.

Do yourself a favor and wait for the stack to be installed, then make a cardboard template. Just sayin'

 

[fossil]

I've never done it...installed a liner and connected it up to an appliance. But I've done a whole lot of other things. Seems like the biggest challenge for most liner installations is that the liners being installed in existing masonry chimneys have to traverse the dreaded smoke shelf to make it to the appliance. Lots of effort is commonly put into cutting out the old damper frame to give the liner an even chance of getting down through there. Just thinking about it, I really think I'd get the liner in all the way first, and then I'd install a two-piece block-off plate around the installed liner. But then, as I said, I've never done it. Rick

 

[Stax]

Cardboard template and block off plate have already been made. No need for two pieces. I will install once liner is pulled through. The first pic is a rough fitting and in the 2nd pic are 2 pices of 3/4" Kaowool that will sit atop the plate.

 

[Jambx]

Well I made my block off plate in 2 pieces only due to the fact I had a piece of 22 gauge that was not large enough to span the damper width. It’s already to go but will take your recommendations and wait for the liner to be installed before I decide where the hole location will be. I will plan to fit the plate around the liner "with the insulation" which will terminate right at the T.

I will post pics a little later but found that making the plate was a lot easier than I initially thought it was going to be – then again I haven’t made the liner hole yet!

One last question – I will be fastening the plate into the brick / mortar joints as well as the metal lintel. Any further comments as to how you did this (screw type, size etc was it self tapping into the lintel / tap-con into brick etc).

Thanks again.

~jim

 

[Wood Heat Stoves]

I would put liner in first and then measure for the hole location. I would make it the size of the pipe and then only put the insulation down to it, not past it.