Wood Stove to Gas Stove

[EddyKilowatt]

Hi Folks...

My previous house is equipped with a small Avalon woodburning stove, installed in a brick fireplace and exhausting up a masonry chimney through a block-off plate and twelve vertical feet of insulated 6" stainless flex liner (single story house).

The house is now occupied by an elderly in-law who is not really up to firing a wood stove, though she loves the heat it makes. I'd like to fix her up with an equivalent freestanding gas stove that would be easier/safer for her to run, something designed for direct vent like the Hearthstone Stowe. There's already an active gas line to the fireplace, that used to run a set of gas logs back before I installed the Avalon.

You guys probably know what question's coming next: How much if any of my existing exhaust system (the block-off plate, 6" stainless liner, and stainless cap) could I use with a gas stove designed for direct vent? Gas stoves I've glanced at, like the Stowe, seem to be designed for a 4" vent... is it out of the question to connect this to a 6" insulated liner designed for wood? (I believe I'd take the intake air from the chimney flue space above the block-off plate, so the cold air would come from the same height as the exhaust vent.)

Having to re-do the vent system won't prevent me from doing this project, but it'll slow it down a fair bit... not to mention I'd hate to undo the work and $$ it took to put all those stainless parts in there, if I don't absolutely have to.

I assume this question comes up all the time but I couldn't locate anything with a search... am interested in any suggestions folks may have regarding the wood --> gas migration path.

thanks,
Eddy

 

[thechimneysweep]

Hey Eddie,

The Stowe uses co-axial vent pipe: a 4" exhaust is wrapped inside a 6-5/8" outer pipe, the space between providing passage for the incoming combustion air. There is a kit that will allow you to use your existing 6" liner as the outer pipe. The kit consists of co-axial fittings for the top and bottom of your liner: you add 4" aluminum flex to connect these two parts, a co-axial rain cap for the top, and whatever short lengths of co-axial pipe you'll need to go from the Stowe to the bottom fitting. Check out sketch #6 on our website at (broken link removed to http://www.chimneysweeponline.com/hodvent.htm)

 

[EddyKilowatt]

Thanks Tom, I hadn't considered that, but after reading around I see that looks pretty straightforward.

Would it be pushing things too far to run the 4" aluminum flex *inside* my 6" stainless pipe? With suitable wind-resistant cap at the top of the 4", and some kind of 6-5/8" to 6" adapter at the bottom?

Eddy

 

[thechimneysweep]

Yep, that's exactly what I was suggesting. Duravent makes a kit that has the fittings for the bottom and top (with a slight modification to fit the single-wall stainless). You add the 4" aluminum flex and a co-axial rain cap.

 

[EddyKilowatt]

Awesome! Thanks for the help. It looks like something like the Conversion Kit A931 on p. 19 of this catalog

(broken link removed to http://www.duravent.com/pdf/dvgs.pdf)

ought to do the trick.

I'll give Simpson a call to verify and to work out the details of the parts list.

thanks!

Eddy