would you use pvc for OAK?

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j00fek

Feeling the Heat
Hearth Supporter
Jun 9, 2008
472
Auburn, Maine
im considering putting an OAK for my nps40.

would you use pvc for this? or what is the preferred piping to use?
 
flexible aluminum, the kind like dryer vent, attached with worm drive clamps
 
I would search the user manual or talk to manufacturer, if you can use a pvc pipe for OAK
In my case like the Rika, the manual tells you explicitly not to use PVC or Aluminum Pipe.
I has to be a metal pipe.
hope this helps you somehow
 
taken from the napoleon nps40 installation manual:

Available from your Napoleon Dealer (114KT)
Outside air must not be drawn from an enclosed space (garage, unventilated crawl space).
NOTE: Wolf Steel Ltd. strongly suggests using outside air for all residential installations, especially for those that
are energy efficient, air-tight homes.
Outside air supply must not be over 15' long.
Outside air vents must be made with 1 3/4" diameter or larger metal or aluminum duct with a metal screen attached to the
end to keep out rodents (P.V.C. or other materials may not be used).
The outside air inlet must not be above or within 12" of the chimney termination, must have a rain cap or down-turned
elbow to prevent the water from entering and be located so that it will not become plugged by snow or other material.
Outside air is mandatory for a combustible built-in enclosure install for the NPI40.

I don't really know what they mean by "metal or aluminum, considering aluminum IS metal. It's like saying, it must be fruit or apples.

you can see the rest of the manual here:
(broken link removed to http://napoleonfireplaces.com/Tech/installation_manuals/NPS40_NPI40.pdf)
 
I would avoid flex pipe except for the final connection or not at all if you can manage it. Flex has a very high pressure drop compared to rigid pipe.
 
orangecrushcj7 said:
I don't really know what they mean by "metal or aluminum, considering aluminum IS metal. It's like saying, it must be fruit or apples.

That is pretty damn funny.
 
May be some one can tell them to change the word metal to steel.
 
I would think that you could go to auto zone or advanced auto and buy the alumunum flex pipe that goes from the bottom of the carburator air filter housing to the exhaust manifold heat shield which is flexable and comes in 1.5, 1.75, 2.0 inch diameter & extends accordian style out to 3 ft That would get you 3 ft away from the stove, which should be far enough to use pvc pipe for the remainder of the run.

They call that pipe the hot air carb intake flex tube & it is very smooth inside so as not to cause air drag & it is also fireproof up to 700 deg which is the melting temp of aluminum.

I have used it on a pellet stove but the pellet stove only gets warm at the cold air intake , maybe 120 deg F. If you are worried about this ,you might be able to attach a 6 inch or 12 inch solid muffler pipe to your cold air intake which would place the aluminum tube far enough away from the stove so as not to exceed its 700 deg temp limit.

A tailpipe piece might even have a 90 deg bend in it so that the pipe ends up pointing in the direction of your run ,should it be to the left or right of the stove.

The hot air carb flex pipe costs about $12.oo & make sure to measure the outside diameter of the cold air intake of your wood stove with a vernier caliber
to bet the proper measurement of od. you can buy a vernier caliber at home depot or lowes or harbor frieght & you dont need a stainless steel vernier, a plastic one is a lot cheaper and addiquate to the task as long as the stove is cold when you measure the pipe od. (plastic melts)
 
Breckwell P23 here. Had my stove installed by dealer. He used PVC for the OAK. However, I noticed the OAK is not ran up to the back of the burnpot, just to the back of the stove. Is this correct? Either way, it does work. Hole was cut through floor to vent under doublewide mobile home.
 
My OAK is 30 ft long but is 4" round fire resistant aluminum flex hose from Home depot . The first 8 ft from the stove is 3" aluminum vent pipe.
 
My OAK is 30 ft long but is 4" round fire resistant aluminum flex hose from Home depot . The first 8 ft from the stove is 3" aluminum vent pipe.
I`d not worry about using PVC for an extended run but I`d not connect it directly to the stove.
 
heres mine, flexible exhaust pipe
 

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Ok, I'm wondering how to put a 2.5 inch pipe through the wall to the outside...securely, and neatly, without some sort of "thimble", like the exhaust vent has? If you just drill a hole in the drywall, and another through the siding/sheathing on the outside, and stick a pipe through...won't it be kind of floppy?
Its hard to cut a perfect hole in drywall...how do you trim that out? just a bead of caulk, or something?

dryer vents typically have a square flange that can be screwed to the siding. but they're too big.

I've seen the pvc vents that are used w/ modern furnaces, but they're attached directly to the furnace. I'm just not getting how you can securely stick a floppy, flexible aluminum tube through a hole in the wall.

Harman sells a couple of kits, but they are ridiculously overpriced for what they are.

On the outside, (vinyl siding), I could use one of those mounting blocks that are meant for attaching an outside light fixture.

I saw that flexible exhaust pipe at Autozone yesterday. wondering how you attached it to the side of the stove pipe? I'm assuming thats what that is in the pic. so...there's a chimney liner inside there, for the exhaust, yes?
 
cac4, I just added outside air to my stove recently.
The outlet on my stove required 2 1/8" pipe. I used
flex exhaust pipe from advance auto. I went from
that, down through the ash trap in the fireplace,
then into 3" flex dryer hose into a 3" dryer vent which
required me to cut a 3 1/4" hole in the side of the
house. From the 2 1/8" pipe to the 3" alum. dryer hose
I used an adapter with hose clamps that I found
at home depot. Used a heavy bead of silicone around the gap
of the hole on the outside and on the inside of the wall.
I pulled the round flap out of the inside of the dryer vent obviously.
There is a cage around the exterior of it to keep out rodents and such.
Fired it up for the first time this season last night and she's working well.

Most importantly, no more cold draft across my floor which p'd me
off because the room would be warm but my feet were cold!

Here's a pic of the stove end and the outside dryer vent.
Didn't take pics of the rest of it in the basement but I think
I explained clearly enough. My total run was approx. 17ft,
but even if you don't have to go that far you can still adapt
a short piece of 3" dryer hose so it will fit onto the exterior
dryer vent with cage.
 

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I couldn't find a 3" dryer vent anywhere. where'd you get that?

and a 2 1/8 to 3" adapter? was that in the area with all the other heating duct stuff? don't remember seeing anything like that, either....

my install should be very "standard". regular drywall--6" stud-wall--plywood sheathing--vinyl siding. should just be a straight shot.
 
The 3" aluminum dryer hose and vent kit I got at Ace hardware.
The adapter I used is rubber and I got that at Home Depot.
That said, the adapter is ugly and unless it was hidden behind
a piece of furniture I don't think I'd want to use it in the main
living space of my house. It's in my basement in my case so it
goes unseen.
 
my whole problem is that the stove calls for a three inch oak but only provides a two inch connection on the stove. the type of adapter is not a common part...
 
donkarlos said:
my whole problem is that the stove calls for a three inch oak but only provides a two inch connection on the stove. the type of adapter is not a common part...

Try your local auto parts store. They should have some
exhaust adapters with a 2" to 3" connector that will work.
 
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