Through the wall

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paullap

New Member
Oct 29, 2022
2
uk
Hi I need some help please, I am installing a new pellet burner 80mm flue and a 50mm air vent . I want to come out of the rear of the stove through a brick cavity wall to a tee, and then strait up the gable end of my house, a few things I need to know please.

Does anyone supply a kit to get through the wall using a 80mm twin wall flue, There must be a clearance around the pie as it goes through the wall.

Once through the wall I was then going to use a single wall flue to save on cost, A 80mm single wall Tee and then up the wall to a Cowell on the top, This is going to be about 8 meters tall, I am being told you cannot do this, any comment would really be appreciated,


Paul
 
All pellet vent through the wall thimbles have built in clearance to combustibles inherent to their design. You cannot use single wall pipe as pellet vent. Depending on the installation instructions provided by your stove’s manufacturer, you probably don’t need to run much higher that 5 feet up the outside wall.
 
I'm pretty sure you'll need the double wall pellet vent pipe from start to finish, this is due to normal build up and protection if there ever should be a fire in the pipe (those pipes do get a glaze occasionally in them) As far as clearance, I'm not really educated in pellet stove things.
 
Hi Thanks for the info, I think I will go a twin wall complete, Does anyone have a links to the thimble to go through the wall, my Flue is 3"bore so I would think the outside would be about 6/7"and the wall thickness is about 300mm.


Paul
 
Oh yeah, I just saw a kit using 3" pellet exhaust vent at Tractor Supply today. 3" is the diameter of the inner stainless steel tube of the pellet vent, then what you see is the outer galvanized steel that I guess is near 3-1/2" or maybe slightly bigger. Thenthere is the wall thimble with it's own telescoping tube. I used just such a double wall pellet vent flue thimble which has inner/outer telescoping tubes to allow for various wall thickness, and cut my 2" holes in a corner to run my 2" OD car exhaust pipe that I had bent for my install as a cold air intake for combustion. 8 meters straight up is over 26 feet, seems like a long way for 3" pellet vent, might be better to jump it up to 4" pellet vent anyway ... to keep those gasses moving. I used to have a 15 foot rise, it worked ... so maybe 26 plus feet will be OK. A few years ago, I redid mine, eliminated the tall upright, have the tee outside about 4 feet from the stove, so figure 2-1/2' outside to tree, then a 5 foot straight up to a 90 and a venturi tip pointed out from under eave. Works at least as well as. You'll want a cap for it too way up there. You will need to run double wall pellet vent the whole way, it ain't cheap.

Pellet stove exhaust is hot and corrosive, and double walled pellet vent cuts down or eliminates condensation problems. That stainless steel is slick aznd will last near forever.
 
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