Horizontal flue - direct vent. Thoughts?

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FlyFish'n

New Member
Oct 23, 2021
62
OH
All,

I am looking at the install manual to the PP60 here and the parts I have and it lines up to a direct vent/horizontal flue pipe install. I am looking through some ideas and it appears a lot of pellet stoves have low horizontal rear flue vent ports so the configuration of the set up (parts, stove) I have here seems like it would line up to be a pretty common set up.

Looking at the manual of the PP60 they show the horizontal/direct vent option:

Horizontal Venting Diagram.jpg


Looking in to direct vent/horizontal venting I came across the following thread discussing this and found the associated following picture:

As captioned in the picture - "Why never to direct vent a pellet stove".

DONOTDIRCTVENT.jpg


Then I find this tip in my manual:

Horizontal Venting Recommendations.jpg


The picture above certainly does not look like to me it is that 18" dimension, but it looks like it would be around the 6" dimension.

So my question is two parts:
1. Would increasing the distance significantly reduce the soot blow-back issue?
2. If you combine the increased distance with a shield of some kind can the soot blow-back/soot accumulation on exterior surfaces be eliminated?

Has anyone done this with any success?
 

Mt Bob

Minister of Fire
Oct 31, 2013
3,983
park county montana
The install in the picture is 1-illegal, 2- stupid, 3- shows a stove with a problem.
Up then out (as in the drawing) is always better, for 3 reasons-- you gain heat inside,from the vertical pipe, it helps with draft, and makes it easier if you ever want or have to change to a different stove.
 

FlyFish'n

New Member
Oct 23, 2021
62
OH
The install in the picture is 1-illegal, 2- stupid
With regards to 1 and 2 - I agree - whoever did that simply cut a hole in the wall and shoved the pipe through, no heat shield/wall thimble.

However, the theory of the horizontal direct vent isn't in and of itself, across the board, "illegal" - it is a legitimately described install method that is in the manual.

Reading through the linked thread there is talk of that horizontal/direct vent method being more of a sales pitch to sell more stoves, but there are some that posted with success direct venting. So I suppose that answers my question - people are doing it, and have done it for years, with success.

Though, if anyone is doing this - do you have pictures of the outside of your set up? I'd be curious if anyone has any soot accumulation on the outside if they are at 18" or better spacing from the exterior wall - with or without a shield?

Looking well above the thick soot coating on the wall in the picture above - it does look like there is some lighter soot accumulation on the siding that extends around and above the thick stuff for quite a ways.
 

Mt Bob

Minister of Fire
Oct 31, 2013
3,983
park county montana
My 1 stove is up and out.About 20" from house,also has a 45 degree "jet type" outlet. No soot, and I get winds on that side,in the winter. But it has only been there 5-6 years?(don't remember). Other stove in basement is into a chimney.