Where to cut hole in wall for Selkirk DT pipe?

[jackiel]

I am having trouble understanding the Selkirk DT pipe installation instructions. Selkirk says to frame out an 8 5/8” x 8 5/8” square for the wall thimble. I trimmed out a lime green 8 5/8” square out of lime green poster board. Look at the poster board square placed on top of the interior side of the wall thimble. It looks as though if I cut an 8 5/8” square opening in the wall, then the opening will be too big for the interior thimble flange pre-drilled holes? What am I doing wrong?
I have attached pics of the pipe in place where I was going to cut the opening. Selkirk says to have a minimum of 4’ from a window. Harman installation instructions say 12” from the side of a window is ok if an outside air kit is used. I am going with the Harman 12” from the window because I am installing an outside air kit.

Maybe I should scrap this plan and should get the Harman straight through the wall kit? I wanted the stove to look like a traditional wood burning stove set up with the 6” black pipe but maybe I’ve made a mistake in buying the Selkirk pipe. It would be an expensive mistake if that’s the case.

It looks like this should work but I worry about the Selkirk termination instructions vs Harman instructions, (48” from a window vs 12”).

What size should I cut the hole for the pipe to go through? 8 5/8” per Selkirk instructions will be too large inside for the interior wall thimble flange.

In the pics of the pipe temporarily in place, I have the wall thimble flange reversed just so I can see it up against the wall.
Maybe I am confusing the 8 5/8” framing with what the interior wall opening needs to be.

 

[jackiel]

More pics

 

[jackiel]

Selkirk instructions

 

[Mt Bob]

1--1' from window is fine especially if the window is inoperable, because of the outside air
2-- The framing spec is merely so that you have proper clearance from the liner,1" all around, does not take into account the fastening, which is no problem on your wall. You could even have a round hole that has 1" clearance,but has to be so that insulation cannot fall down on the liner. Some have used a sheet metal tube.

 

[gfreek]

My Direct-Temp pipe, cut hole round big enough for the thimble I believe, forgot size but here is a pic..measured and re measured and test fit multiple times..better to small a hole than too big,
BTW, my first cut I hit an old window header as you can see..!!

 

[jackiel]

Thanks for the replies but I’m still not clear on the size the hole needs to be for the 1” clearance. Is the hole supposed to be 1” larger than the wall thimble ?

 

[Mt Bob]

I believe that thimble is different than what the instructions are for.Got a part number for it? Because from what I can see, if your pipe itself is spaced 1" from the liner,inside, the hole would only have to be the size of the outside of the liner "pipe" circle, being the flue pipe itself has incoming air in the outer shell. Don would know, but haven't seen him around.

 

[jackiel]

I was thinking the same thing on the inner liner and outer liner of the wall thimble. It looks like cutting the hole just big enough for the outer liner should work. Part# is 4DT-WT wall thimble which was included in the 4DT-VPHKB Up and Out kit.

 

[Mt Bob]

OK the directions say-
"This two-piece wall thimble easily slides together for installation on wall thicknesses of 4" to 7". This serves a dual purpose as both a heat shield and firestop."
Which would tell me you only need it as big as we discussed, as insulation can lay against a firestop.
That is my opinion.and how I would do it. Pellet pipe does not get hot as wood stoves, and with incoming air,will be even cooler.
But others may say different.

 

[gfreek]

Yes mine is the 4DT-WT wall thimble.. IMO, cut the hole just large enough for the larger collar to fit. The outer shell of DT pipe does not get hot.. Be sure you have framing or such in the wall to secure the inner flange, I believe what they want by the 8 5/8 x 8 5/8. Stupid question but , Could you have the wall thimble for the multi fuel assembly ??

 

[Mt Bob]

Yes mine is the 4DT-WT wall thimble.. IMO, cut the hole just large enough for the larger collar to fit. The outer shell of DT pipe does not get hot.. Be sure you have framing or such in the wall to secure the inner flange, I believe what they want by the 8 5/8 x 8 5/8. Stupid question but , Could you have the wall thimble for the multi fuel assembly ??

Thanks,I knew someone here would have already been through this.
Also,if that wood nailed paneling is 1/2" or better, I would not even worry about framing inside the wall.

 

[gfreek]

Thanks,I knew someone here would have already been through this.
Also,if that wood nailed paneling is 1/2" or better, I would not even worry about framing inside the wall.

Yes great point

 

[jackiel]

I was just he ready to post about not even framing inside the wall because of the 3/4” shiplap pine on the inside wall. I fabricated the green poster board to represent the pipe to have to trace around the outer diameter. Got the pipe tied to screws to hold it in position to mark it.

 

[Mt Bob]

Yep,cut 2 circles and should be good to go. Level or a tad uphill. Don't forget(lots do) insulation on the inside and outside covers, and sealer after you install the pipe,around the pipe. Or, because of only cutting circles, sealer around the covers/thimble liners, but that makes it hard to remove in the future,if necessary. You can now buy liotherm sheet gasket very cheaply.