Venting a Pellet Stove (Harman XXV)

[Ed in Maine]

Just got an XXV to replace my Resolute, no more time to cut wood.. (but my MS361 is ready on a moments notice!).
What's the scoop on venting this baby. It is on a stone hearth, going up a field stone chimney (7" flue, about 5' off the hearth). What guage pipe? Does it need to be seamless? I know they recommend double walled seamless "PL", but this is going to be a couple feet from any combustibles. Was even considering having a buddy tig up a stainless pipe. What are my options? Want to keep it under $150 or so. Getting the pipe from the harman dealer was going to be over $300! After spending $3k with him, I said I was going to give the vent a shot on my own.

Great forum, looking forward to more posts!
Ed

 

[HarryBack]

Edster......Id stick with PL vent, even though its more money than 22 or 24 gauge smokepipe. The XXV is a positive pressure (forced draft) applicance, and PL vent was designed to work in a positive pressure environment. The smokepipe most folks use for woodstoves is intended to be used in a negative pressure environment (natural draft), so you might find it leaks. That being said, the XXV also has a topvent option, which does use regular smoke pipe. If you do decide to use the regular pipe, make sure you seal it well with RTV silicone.

 

[Ed in Maine]

Thanks for the reply Harry. I agree, positive pressure is something keep in mind, but my oil furnace down cellar is blower driven as well and it is just 7" galvi stove pipe with no silicon. Granted, it is down cellar, 32' below atmo press and drafting like crazy, and not in a 'living area', but it has a stack temp of 350F.
I saw the top vent option for the XXV, looked nice but I was afraid to ask a price, I bet it was $250!

My latest throught was to use some schedule 10 Sprinkler piping and use a hydraulic bender to put a nice bend at the top. No seams, and it would look nice. Just thinking out loud.

Why kind of stack temp will this XXV be running?

Ed

 

[HarryBack]

Thanks for the reply Harry. I agree, positive pressure is something keep in mind, but my oil furnace down cellar is blower driven as well and it is just 7" galvi stove pipe with no silicon. Granted, it is down cellar, 32' below atmo press and drafting like crazy, and not in a 'living area', but it has a stack temp of 350F.
I saw the top vent option for the XXV, looked nice but I was afraid to ask a price, I bet it was $250!

My latest throught was to use some schedule 10 Sprinkler piping and use a hydraulic bender to put a nice bend at the top. No seams, and it would look nice. Just thinking out loud.

Why kind of stack temp will this XXV be running?

Ed

Sprinkler pipe? I have no idea what that is, but Im leery of it since it isnt really for that use, and as a dealer, I certainly cant stand behind or reccommend a product which isnt designed for that use.

Stack temps of a few hundred degrees wouldnt be unheard of for the XXV.

As for the top vent option, I dont recall what it costs, but it isnt cheap.

 

[Xena]

I'd recommend doing it right the first time and use the PL.
If you do it yourself you'll save the labor costs
and you'll avoid having to spend more money
later down the road to re-do if something winds
up not quite right.
After dropping 3 grand on the unit, it's worth it to
spend a couple more greenbacks to vent it with the recommended
stuff and be done with it, no? Good luck!

 

[Ed in Maine]

Sprinkler pipe is just thin wall pipe, what you'd use to run sprinkler lines through a commercial building, comes in 1in to 14in dia. Would just be easy to put some nice bends in it since it is thin wall.

You both bring up good points, especially for my first pellet stove. Last thing I want my dealerto say is "you used what to vent it?? I cannot warranty that...."
Will let you know what I end up doing, thanks again,
Ed

 

[Corie]

With all due respect Ed, installed a pellet stove really isn't an opprtunity to fabricate some unique method for venting. Use the pipe being sold for use in pellet installations and install it to the manufacturers recommendations.

 

[MountainStoveGuy]

Sprinkler pipe is just thin wall pipe, what you'd use to run sprinkler lines through a commercial building, comes in 1in to 14in dia. Would just be easy to put some nice bends in it since it is thin wall.

You both bring up good points, especially for my first pellet stove. Last thing I want my dealerto say is "you used what to vent it?? I cannot warranty that...."
Will let you know what I end up doing, thanks again,
Ed

thats EXACTLY what your dealer will say...

 

[moog5]

I paid $225 for the XXV top vent adapter plus $140 for a 50-90SS (telescoping) single wall pipe, to existing 6"triple wall pipe in a ceiling box. The adapter makes the exhaust look like it is coming out of the top of the stove, rather than up from the back (simliar to a VC Resoute Acclaim, which was what I took out and replaced with a Whitfield in 95' prior to replacing that with the XXV last year). See this link for a picture of mine.

https://www.hearth.com/talk/threads/4481/