# To OAK or not to Oak



## Tonyray (Jan 16, 2014)

_Stumbled across this a while back and wondered what others thought about it and if
it still holds true since many here are insulated up the whazoo and seem to feel they are keeping all heat from the stove inside the house with no problems of negative pressure._

From the 70's up through the early 90's home construction made significant leaps and bounds. In the 70's or earlier if you took all the air leaks in a home and added them together you would end up with approx. a 3' diameter hole in your wall! Todays construction however is so tight if added all the leaks it would amount to approx. a 3" diameter hole BIG difference. Also in the envelope of the home you have all these appliances taking air out of the home. Dryers, ventahoods, CH/A, and yes even the fireplace just to name a few and nothing is bringing air in so eventually you end up with a negative preassure in the home or a vaccumm if you will and the home will take a breath where ever it can. Because of this hearth designers and manufacturers have come up with outside combustion air kits to offset the negative preassure. sometimes its not enough to overcome it but does help in the stove efficency if the home is really tight.


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## Ctcarl (Jan 16, 2014)

Good read


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## Defiant (Jan 16, 2014)

Nice, my house was built in the mid 90's, no OAK for the XXV, straight out application and has worked great


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## mikkeeh (Jan 16, 2014)

Find a neighbor that has an OAK.   Hold your hand over it while the stove is running and take note of how much air is flowing.  You are merely circulating outside air through the stove.   Now .....imagine all the air that the OAK is moving, is HEATED air that it is sucking out of your house.  This is your stove without an OAK. Now...while your stove is sucking your HEATED air out of the house..the house becomes a negative pressure zone...and sucks COLD air from outside in to replace it.  Similar to leaving your bathroom exhaust fan all the time.     Maybe its just me.....but it seems to be a no-brainer.


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## P38X2 (Jan 16, 2014)

mikkeeh said:


> Find a neighbor that has an OAK.   Hold your hand over it while the stove is running and take note of how much air is flowing.  You are merely circulating outside air through the stove.   Now .....imagine all the air that the OAK is moving, is HEATED air that it is sucking out of your house.  This is your stove without an OAK. Now...while your stove is sucking your HEATED air out of the house..the house becomes a negative pressure zone...and sucks COLD air from outside in to replace it.  Similar to leaving your bathroom exhaust fan all the time.     Maybe its just me.....but it seems to be a no-brainer.


Well stated.

It's not just you.


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## Madcodger (Jan 17, 2014)

Defiant said:


> Nice, my house was built in the mid 90's, no OAK for the XXV, straight out application and has worked great


The flame of the stove is not affected by an OAK (or lack of it) if it can get air from somewhere.  It really doesn't care whether you give it FREE outside air or heated (already paid for) air.  So the fact that your stove "has worked great" is like saying your car will do 70 even with the parking brake on.  Great engine, no doubt - but how's that gas mileage?

And for what it's worth, most contractors I've seen have about as much understanding of air sealing as they have of rocket science.  Having a home built in the 90's - or even yesterday - comes nowhere near assuring a homeowner of a "tight" home unless a blower door test by a BPI or RESNET auditor is conducted.  Yes, newer homes are moderately "tighter", often due to better materials.  But unless they are used effectively, people would be shocked at what they are losing from air leaks.


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## Tonyray (Jan 17, 2014)

Madcodger said:


> The flame of the stove is not affected by an OAK (or lack of it) if it can get air from somewhere.  It really doesn't care whether you give it FREE outside air or heated (already paid for) air.  So the fact that your stove "has worked great" is like saying your car will do 70 even with the parking brake on.  Great engine, no doubt - but how's that gas mileage?
> 
> And for what it's worth, most contractors I've seen have about as much understanding of air sealing as they have of rocket science.  Having a home built in the 90's - or even yesterday - comes nowhere near assuring a homeowner of a "tight" home unless a blower door test by a BPI or RESNET auditor is conducted.  Yes, newer homes are moderately "tighter", often due to better materials.  But unless they are used effectively, people would be shocked at what they are losing from air leaks.


So the concensus here so far is having an OAK covers the bases without any guess work...


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## newbieinCT (Jan 17, 2014)

mikkeeh said:


> Find a neighbor that has an OAK.   Hold your hand over it while the stove is running and take note of how much air is flowing.  You are merely circulating outside air through the stove.   Now .....imagine all the air that the OAK is moving, is HEATED air that it is sucking out of your house.  This is your stove without an OAK. Now...while your stove is sucking your HEATED air out of the house..the house becomes a negative pressure zone...and sucks COLD air from outside in to replace it.  Similar to leaving your bathroom exhaust fan all the time.     Maybe its just me.....but it seems to be a no-brainer.


very helpful! Thanks!
Just got an OAK intalled w/ my p61a today and I tried to explain to my dad why we got it and I muddled it up. I'll use this example next time we talk


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## Harvey Schneider (Jan 17, 2014)

I like to make things visual. 
If your stove uses 100 cfm for combustion and it pulls that from the house. That is a volume 10 feet by 10 feet by 60 feet every hour. Or visualize it as a 12 by 12.5 room with 8 foot ceilings, every two hours. All of that air is coming in as leaks and drafts from windows, door,outlets and improperly sealed seams.


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## Bridgeman (Jan 17, 2014)

My house was built in 1988 and leaks a small amount of outside air at every window and door. My pellet stove, oil boiler and clothes dryer send heated outside at an alarming volume. I wonder what the savings in pellet use would be with an OAK? Everything is toasty and warm and I burn about a bag of pellets a day. Would the savings be worth the effort of drilling down through the brick hearth and 10'  to the outside wall? With all the problems with ice and condensation I read on this site I have my doubts. I have access to a diamond core drill and am capable of getting it done. As an alternative, Is there a coaxial vent pipe I can run up the 8"X8" flue? The run to the top of the flue is about 18'. I currently run the exhaust gas out old school up the flue and the Harmon works great. I'm not inclined to fix a problem that does exist only to create a new ones like icing and restricted air flow leading to poor combustion.


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## Defiant (Jan 17, 2014)

Bridgeman said:


> My house was built in 1988 and leaks a small amount of outside air at every window and door. My pellet stove, oil boiler and clothes dryer send heated outside at an alarming volume. I wonder what the savings in pellet use would be with an OAK? Everything is toasty and warm and I burn about a bag of pellets a day. Would the savings be worth the effort of drilling down through the brick hearth and 10'  to the outside wall? With all the problems with ice and condensation I read on this site I have my doubts. I have access to a diamond core drill and am capable of getting it done. As an alternative, Is there a coaxial vent pipe I can run up the 8"X8" flue? The run to the top of the flue is about 18'. I currently run the exhaust gas out old school up the flue and the Harmon works great. I'm not inclined to fix a problem that does exist only to create a new ones like icing and restricted air flow leading to poor combustion.


 The downside of OAK is pulling moisture from the outside through your stove, for your chimney application they make a termination cap that is easy to install. I have run my stoves for the past 16 yrs. without oak, maybe I need to do more research. I am also 50 ft. from a brackish water tidal river.


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## Bridgeman (Jan 17, 2014)

So you suck cold air down the flue an some kind of trick set up to get through the thimble and into the intake on the stove?


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## Harvey Schneider (Jan 17, 2014)

Defiant said:


> The downside of OAK is pulling moisture from the outside through your stove,


Please explain.
Cold outside air should have less moisture in it than warm, humidified inside air.


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## Defiant (Jan 17, 2014)

My indoor humidity runs a consistent 30+%, you should be familiar with CT weather, last week during all that rain outside relative humidity was 98+%.


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## Madcodger (Jan 17, 2014)

I give up...  Do as you wish, ye doubters of OAK. OAK, no OAK, do whatever you've convinced yourself works.  You can buy simple devices that measure humidity at a given temperature, but if you think the cold air is wetter, so be it.  The moon can be made of cheese for you if you wish, and the snowflakes can be fairy tears.  

This must be how my wife feels when she tries to teach me to cook. Seems as simple to her as falling off a log, and it just doesn't gel in my brain.  The same is evidently true of physics for some.


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## Greenhorne (Jan 17, 2014)

newbieinCT said:


> very helpful! Thanks!
> Just got an OAK intalled w/ my p61a today and I tried to explain to my dad why we got it and I muddled it up. I'll use this example next time we talk



Can someone enlighten me why if an outside air kit makes a pellet stove somehow more efficient/ heat better/run better (not talking mobile home here).... why would there not be a similar setup recommended/widely used  for a woodstove/wood boiler. I really can't see any benefit unless your home is so tight that when your wife farts at night while sleeping... the sudden increase in pressure airlocks the house and now you cant open the door in the morning without cracking a window first.... 

I know that is a bit much there but you get my point... I don't think it is necessary or really any benefit for an OAK in most homes. I have not seen anything beyond Mcguyver engineering experts to support the need or the actual benefit of an OAK.

Welcome any real study data that anyone has to support the need/benefit.... 

Thanks and not flaming just commenting on what I have not seen to be proved as fact


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## BrotherBart (Jan 17, 2014)

Besides the long established fact that cooler, denser air makes for more complete combustion:

http://chimneysweeponline.com/hooa.htm 

Wood stoves should have'em too. Wish I had the guts to bore the hole in the back of my fireplace.


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## Mt Bob (Jan 17, 2014)

I like cold hard facts also,so I will pass one on-cold ouside air supplied to a building and heated up inside will lower the relative humidity inside.Not from me,from enginerring handbook.Also found if your inside humidity is too low you have air intrusion(leaks).


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## BrotherBart (Jan 17, 2014)

And what no pellet stove manufacturer's lawyer will ever let them admit is that if the stove quits because of a power failure or whatever the dinky chimney most people use with them can easily turn into the intake and the stove intake become the exhaust and flood the joint with CO.


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## GeHmTS (Jan 17, 2014)

Good luck on your data search, you'll need it.  It's probably needed in the most extreme cases where other appliances may be pulling the same air as the stove and chocking the flame.  For the most part, it's just a waste of $$$.  I bought my stove, installed it myself through an existing chimney without OAK and my own vent pipes.  My stove works fine with no issues and burns well.  Every year I get my chimney cleaned, the sweeper tells me that I need a liner to get the BTUs out of the stove.  Every year I politely decline.  He also recommended that I have an OAK so it runs efficiently.  Again I decline and mention the fire looks great.  He finally recommended that I change the vent pipes to my stove.  I finally told him that I will *NOT* have him return if he tries to sell me one more thing.  He now does the chimney sweep only.

I have come to realize that when people find out that you're willing to spend $$$ on a stove, car, house, or whatever, they will push other unnecessary accessories on you.  It's kind of like going to the dentist to get your teeth clean, and the dentist is asking you why you still have your wisdom teeth.


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## Madcodger (Jan 17, 2014)

Greenhorne said:


> Can someone enlighten me why if an outside air kit makes a pellet stove somehow more efficient/ heat better/run better (not talking mobile home here).... why would there not be a similar setup recommended/widely used  for a woodstove/wood boiler. I really can't see any benefit unless your home is so tight that when your wife farts at night while sleeping... the sudden increase in pressure airlocks the house and now you cant open the door in the morning without cracking a window first....
> 
> I know that is a bit much there but you get my point... I don't think it is necessary or really any benefit for an OAK in most homes. I have not seen anything beyond Mcguyver engineering experts to support the need or the actual benefit of an OAK.
> 
> ...


OK, I can't resist...  Seriously?  You want a study??  You have a combustion device...  That requires air.  That air is being actively pumped into the combustion chamber and almost immediately after the reaction we call fire occurs, it is actively pumped outside.  PUMPED outside, because that's what a combustion blower does!  Air comes in, combustion occurs, air goes out.  

What temperature is that air going into the combustion chamber UNLESS it is being pulled in DIRECTLY from outside?  How about ROOM temperature?  And how did it become room temperature?  Is there a magic supply of room temperature air reserved just for the stove?  No, YOU HEATED IT to room temperature!  And by actively pumping that air into the stove and back out, what you are doing is increasing the RATE of air changes that occur.  For just this chain of events, It frankly doesn't matter whether your house is "tight" or drafty if a sufficient volume of cold air can be obtained (and if the stove burns, there is sufficient volume).  Either way, you are accelerating the RATE at which you bring in cold air, heat it, and pump it back out.

Honestly, I am just at my wits end with people who can't grasp this.  There is just no way to help you...


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## thadd677 (Jan 17, 2014)

This is my first season with a pellet stove and I didn't install an OAK.  Now I have cold air getting pulled in through the vent by my cooktop in the kitchen, as well as other areas of the house.  Next season I will definitely be installing an OAK.


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## BrotherBart (Jan 17, 2014)

Ya ain't gonna believe what happens with a basement install of any stove without an OAK. Stack effect in the house kicks yer butt. While it pulls heat upstairs it sucks cold air in from everywhere in the basement.


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## Greenhorne (Jan 17, 2014)

bob bare said:


> I like cold hard facts also,so I will pass one on-cold ouside air supplied to a building and heated up inside will lower the relative humidity inside.Not from me,from enginerring handbook.Also found if your inside humidity is too low you have air intrusion(leaks).



An actual engineer(one I have known for many years and trust) once told me houses... average houses refresh/leak about 60 % of their air every 15 minutes and we don't necessarily feel this because it is largely happening on the exterior margins of the home(attic, windows, doors, bathroom vent/vents, cookstove vents, etc.)... part of this is by design as the home needs to breathe and part is from inefficiencies. I have this weekend off so I will do some digging for some real data studies and not opinion based on opinion/generalities. I am not saying an OAK is completely wasted money spent as it is def a sure bet if you think you may have a tight home, but... I don't think it translates to guaranteed better efficiency, air quality, etc. in every case.


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## Greenhorne (Jan 17, 2014)

BrotherBart said:


> Ya ain't gonna believe what happens with a basement install of any stove without an OAK. Stack effect in the house kicks yer butt. While it pulls heat upstairs it sucks cold air in from everywhere in the basement.


I think that would be very relevant, and also a bit of a different situation in that a basement is largely more air tight than an above ground structure.... in general.


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## BrotherBart (Jan 17, 2014)

Greenhorne said:


> I think that would be very relevant, and also a bit of a different situation in that a basement is largely more air tight than an above ground structure.... in general.



Not any one that I have ever seen.


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## Harvey Schneider (Jan 17, 2014)

There is nothing harder to open than a clenched mind.


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## GeHmTS (Jan 17, 2014)

That sounds like something Einstein would say.  Pure genius


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## P38X2 (Jan 17, 2014)

When warmer weather comes, and on a calm day, open the window closest to your clothes dryer 1/4". Now, light a piece of stick incense and hold it near the opening in the window. Maybe the smoke will drift out slowly, maybe it'll blow back into the room slowly, maybe it'll go straight up. Take note of what it's doing. Now, go turn the clothes dryer on and repeat the test. Wow, weird! Lots of air coming in! Where does that air come from when the window is shut? Ya, the same places it comes from when yer stove is running. The only difference is instead of it being nice balmy 70° air, it's 30 or 10 or worse. And now that you're bringing the outside temps in (something you're trying to fight off burning your stove in the first place), go turn your stove up higher and burn even more pellets.

Do you need an OAK for your stove to run successfully? Not in 99.99999% of the cases. Will it heat your space more efficiently WITH an OAK? Hmmmmm...

Of course, run your stove how you'd like. You're still saving a ton of $$$$ over oil or gas, but you're also decreasing the effectiveness and efficiency of your stove, and creating all sorts of drafts in the process. Like what's been written a hundred times before, the combustion air HAS to come from somewhere, and unless you have oxygen tanks hooked up to your stove, it's coming from OUTSIDE. PERIOD.

Does anyone really need top men doing scientific research to verify this concept?


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## Greenhorne (Jan 17, 2014)

again


Madcodger said:


> OK, I can't resist...  Seriously?  You want a study??  You have a combustion device...  That requires air.  That air is being actively pumped into the combustion chamber and almost immediately after the reaction we call fire occurs, it is actively pumped outside.  PUMPED outside, because that's what a combustion blower does!  Air comes in, combustion occurs, air goes out.
> 
> What temperature is that air going into the combustion chamber UNLESS it is being pulled in DIRECTLY from outside?  How about ROOM temperature?  And how did it become room temperature?  Is there a magic supply of room temperature air reserved just for the stove?  No, YOU HEATED IT to room temperature!  And by actively pumping that air into the stove and back out, what you are doing is increasing the RATE of air changes that occur.  For just this chain of events, It frankly doesn't matter whether your house is "tight" or drafty if a sufficient volume of cold air can be obtained (and if the stove burns, there is sufficient volume).  Either way, you are accelerating the RATE at which you bring in cold air, heat it, and pump it back out.
> 
> Honestly, I am just at my wits end with people who can't grasp this.  There is just no way to help you...



I understand your position completely however is it your contention that with an OAK installed vs the same situation with no OAK that a substantial volume of already heated air is conserved to the point that the continual loss of air/heat through convection is marginalized so much that the OAK is compensating enough so that the normal heat/air loss is is surpassed and makes the modification justifiable or is it insignificant unless you have a really tight home? That is where I am going with this.


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## Mt Bob (Jan 17, 2014)

Good stuff guys,would have an oak if pratical.More insight,doctors discovering more health problems in tightly sealed houses,no air exchange.European stoves sometimes do not have sealed oak connection to let house breath.Just more info.


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## P38X2 (Jan 17, 2014)

I will also agree with Defiant, to an extent, that an OAK can introduce humidity to the inside of the stove. But in the case of a stove in operation, it's irrelevant. When it absolutely poses an issue is in the off season, as it facilitates a nice convection loop to set up shop and accelerate the formation of rust. In that case, the solution is to plug the the termination and OAK intake. Damp Rid in the firebox works well too. DON'T forget to put everything back in "burn mode" come heating season! At the end of the burn season, I unplug the stove and put a nice big piece of painters tape on the plug as a reminder.


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## THE ROOSTER (Jan 17, 2014)

P38X2 said:


> Well stated.
> 
> It's not just you.


Agreed


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## Greenhorne (Jan 17, 2014)

BrotherBart said:


> Not any one that I have ever seen.


I am assuming a below ground basement... bad assumption on my part.


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## P38X2 (Jan 17, 2014)

bob bare said:


> Good stuff guys,would have an oak if pratical.More insight,doctors discovering more health problems in tightly sealed houses,no air exchange.European stoves sometimes do not have sealed oak connection to let house breath.Just more info.


Well maybe if you have a ziplock bag over your house. You're still gonna have leaks. That, in combination with everyday exterior door use, will probably create enough of an air exchange to keep things healthy. I'd think you'd really have to do an INSANE amount of air sealing to cause serious health issues.


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## BrotherBart (Jan 17, 2014)

Greenhorne said:


> I am assuming a below ground basement... bad assumption on my part.



The sills plates are always going to be above ground. The major sources of leaks. But I find new ones in my below grade basement all the time.

I'm out of this one. The OAK for my pellet stove in the basement cost me $23. I ain't looking back.


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## Mt Bob (Jan 17, 2014)

P38X2 said:


> Well maybe if you have a ziplock bag over your house. You're still gonna have leaks. That, in combination with everyday exterior door use, will probably create enough of an air exchange to keep things healthy. I'd think you'd really have to do an INSANE amount of air sealing to cause serious health issues.


 That is my point,what you are thinking is what people thought for years,and are finding out different.I lived in a 1/2 house,upstairs,super sealed,radiant ceiling heat back in the mid 80's.In winter,had to air out house(open all doors and windows)once a week.If I farted,same thing,would not go away.I'll take my drafty old log cabin any day.


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## Dr.Faustus (Jan 17, 2014)

I bought my pellet stove and then i read here i should install an OAK. at first i didnt think it was necessary, but after reading how everyone swears by it, i went out and got an OAK. Shes a real beauty. Planted it right in the backyard. It's about 20 feet tall. I'm not sorry i got this OAK but i must say i really dont notice a difference in the house?
The house however is a bit cooler in the summer due to the shade. Is there a specific spot this oak should be planted to make a difference?


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## P38X2 (Jan 17, 2014)

bob bare said:


> That is my point,what you are thinking is what people thought for years,and are finding out different.I lived in a 1/2 house,upstairs,super sealed,radiant ceiling heat back in the mid 80's.In winter,had to air out house(open all doors and windows)once a week.If I farted,same thing,would not go away.I'll take my drafty old log cabin any day.


Ok, point taken. However, a non-OAK setup is not a good way to facilitate air exchange. WAY too much volume and way too inefficient. Not really sure how they work, or what they're called, but there are units that can be installed to efficiently get the job done. Air exchangers, maybe? Idk.


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## BrotherBart (Jan 17, 2014)

Dr.Faustus said:


> Is there a specific spot this oak should be planted to make a difference?



I have a suggested place.


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## Dr.Faustus (Jan 17, 2014)

BrotherBart said:


> I have a suggested place.


Ouch! heh saw it comin


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## ZBrooks (Jan 18, 2014)

Greenhorne said:


> I really can't see any benefit unless your home is so tight that when your wife farts at night while sleeping... the sudden increase in pressure airlocks the house and now you cant open the door in the morning without cracking a window first....



Tears of laughter!

I'd rather push warm air out through the leaks in my house rather than draw cold air in through them.  My OAK was less than $25.


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## Bridgeman (Jan 18, 2014)

I agree with the obvious conclusion that an OAK must be more cost effective. The question is, how much? Is it 2% or 20%?. I suspect there are so many variables that it would be almost impossible to calculate without constant monitoring of a dozen factors. At a burn rate of 150 bags of pellets a year is it a 3 bag savings or a 30 bag? I haven't seen any hard data at this point. If it is a difference of 10 more bags a year, is it worth the expense and extra plumbing to clean and maintain? My OAK install is not a simple affair and requires big expense and a visual impact bordering on industrial. The fart test, though interesting, is hard attach a bag count to. Greenhorne is saying the same thing and yes I do want to see a study before I commit my hard earned dollars.


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## St_Earl (Jan 18, 2014)

^it's not only cost, but comfort too.
we sit on the carpet in the stove room when we hang out there. backgammon etc...
without the oak there was a very uncomfortable cold flow of air along the floor moving toward the stove.
now there's not.
even with the floor fan on low blowing in, it's not cold like it was pre-oak.

our house is in no danger of being "too tight".
positive pressure ftw!


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## Madcodger (Jan 18, 2014)

OK, FOR THOSE WHO WANT PROOF OR COST OF NO OAK - CALCULATE IT FOR YOURSELF

Alright, let's solve this once and for all...  It will probably decrease Webbie's server load enough to make this worthwhile, so here goes...  

First, for those of you who think this is about whether your stove, "works just fine" without an OAK, that is not our argument or point.  We understand that you have enough air to allow for combustion and that you are staying nice and toasty.  We are not arguing that.  We are arguing that you are using more pellets than necessary to stay nice and toasty.  So to help out those new to pellet heating, and save some of us from the rest of you driving up the cost of pellets because you throw supply and demand out of balance (I am about half joking there, but only half), here is your ability to calculate this, for yourself, as long as the very nice people at Lincoln Electric keep their online heat loss calculator up and running.  I don't have any relationship to that company, but understand that they make welding equipment, industrial automation products, and other such things.  Go buy something from them or tell someone that welds or automates factories how helpful they are, and get them to buy something, and you can calculate guilt free...  But before you get started, some information you will need:

*CFM (cubic feet per minute) of your pellet stove blower*.  If you don't know, many are about 80.  And if you think yours is more efficient, use half of that, or 40 CFM.  This is the amount of air your stove is pulling in from outside, using for combustion, and then pumping back out.  If you have a pellet stove and no OAK, you are accelerating the rate at which your house exchanges air by this amount.  When your pellet stove is not running (or if you have an OAK), then your house is exchanging air at a rate that is this much less per minute.  This is a very important point, and is the basis of the whole reason behind an OAK.

*Hours Worked Per Week *(this is the number of hours your stove operates per week)

*Available BTU per Unit*.  Most agree that pellets have about 8,000 BTU per pound.  Yes, there are some that are more than that, maybe 8200 - 8400.  But once you figure in a bit higher moisture content from sitting around the box store lot or your house, you are probably a bit lower than 8,000.  So use what you want, but 8,000 is fairly generous.

*Cost of Fuel per Unit*.  How much do you pay for a pound of pellets?  At $250/ton, that's $0.125.  At $229, $0.1145.  At $200, $0.10 (and I'm skeptical that you're getting 8,000 BTUs from that pellet, but whatever...  Keep on rolling along here)

*Degree Days per Year*.  I do not have time to go into degree days in depth here, but think of it as the average difference between the temperature of the air outside and the temperature you want your house to be, multiplied by the length in days of your heating season.  (For those of you into weather calculations stop twitching at that oversimplification and let's move on - we're just trying to help people calculate something here, not pass a meteorology exam).  YOU DO NOT NEED TO CALCULATE THIS - IT IS AVAILABLE IN TABLES ON THE SITE THAT HAS THE CALCULATOR.  Where it asks for "Air Temp", that's the temperature you want your house to be.

N*ow, here is the link to that calculator:* http://content.lincolnelectric.com/products/automation/heat-loss.asp

I figured out that one of my stoves would cost me about $80 - $130 per year, depending on how long I ran it, without an OAK.  Multiply that by several years, and it adds up.  I bet if you were taxed by that amount you'd go crazy, and that's essentially what you're doing without an OAK - taxing yourself by buying an excessive amount of pellets.

So there, knock yourself out.  Calculate for yourself.  And thank the people at Lincoln Electric.  I think I may go take up welding or something...


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## Harvey Schneider (Jan 18, 2014)

Defiant said:


> My indoor humidity runs a consistent 30+%, you should be familiar with CT weather, last week during all that rain outside relative humidity was 98+%.


That is *relative humidity*. It doesn't mean the same thing unless it is at the same temperature. Unless you have a dehumidifier running in your home during winter, I guarantee that the air in your home contains more water than the air outside.


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## Defiant (Jan 18, 2014)

Harvey, I run a humidifier near the pellet stove and a large cast iron kettle on the wood stove to keep the moisture levels at 30%.


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## Bridgeman (Jan 18, 2014)

I ran the numbers and for my situation it looks like $150 to $200 per heating season. That is about 25% savings for an OAK instalation.. Does that assume no air infiltration in the heated space? It seems the numbers are to good to be true. Any engineering types out there to give an opinion on the calculation? If the numbers are good, it is definitely worth the effort.


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## Harvey Schneider (Jan 18, 2014)

Defiant said:


> Harvey, I run a humidifier near the pellet stove and a large cast iron kettle on the wood stove to keep the moisture levels at 30%.


I said *de*humidifier.

I don't mean to be rude, but do you understand the concept of *relative *humidity?


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## Defiant (Jan 18, 2014)

Harvey Schneider said:


> I said *de*humidifier.
> 
> I don't mean to be rude, but do you understand the concept of *relative *humidity?


I guess not, I have a digital instrument that measures outside and a few other manual ones that measure inside.


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## Harvey Schneider (Jan 18, 2014)

Defiant said:


> I guess not, I have a digital instrument that measures outside and a few other manual ones that measure inside.
> View attachment 124359
> View attachment 124361


Here is a very brief explanation of relative humidity. It basically is a measure of how much of the air's capacity to hold moisture has been filled. That capacity changes with temperature.
An example below.



Harvey Schneider said:


> The air has the same amount of moisture in it before and after it is heated. If the air outside at 10 degrees, for example, has 70% relative humidity, when heated, it's capacity to hold moisture increases. Because of that, it's relative humidity drops (to, perhaps 30%). It still contains the same amount of moisture, it's just that it could hold more. It will take that more from wherever it can find it; from the furniture, from house plants or from you.


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## mikkeeh (Jan 18, 2014)

Wow:::  I posted early in this thread, with what I thought was a logical argument for OAKS.  I see there are folks that don't accept logic.  Some folks are looking for scientific studies.    Its been scientifically proven that smoking is hazardous to your health, and cost the taxpayers billions in healthcare....but people still do it????   Drinking and driving kill people and ruins lives....people still do it.  There are folks that will not change their minds....and will not use logic...... And "common sense" isn't very common these days.   But everyone has a choice.    I choose to use and OAK.  You do whatever floats your boat.


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## St_Earl (Jan 18, 2014)

Madcodger said:


> Alright, let's solve this once and for all...


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## Madcodger (Jan 18, 2014)

Bridgeman said:


> I ran the numbers and for my situation it looks like $150 to $200 per heating season. That is about 25% savings for an OAK instalation.. Does that assume no air infiltration in the heated space? It seems the numbers are to good to be true. Any engineering types out there to give an opinion on the calculation? If the numbers are good, it is definitely worth the effort.


The existing air infiltration is essentially not part of the equation.  All an OAK does is take the active pumping of internal air to the outside (through your stove) out of the equation, leaving you with the same air exchange (in and out) you had without your stove running.  In other words, it closes that loop and separates your stove's combustion cycle from the existing air exchange of your home without the stove.  That's its whole purpose for existing - to leave you with the same rate of air exchange rather than an accelerated rate.

As for the numbers being "too good to be true", I cannot help you.  If you want to spend the time checking the calculator's accuracy, a number of physics texts can likely supply the various formulas.  I'm going to trust the folks that built that calculator on this one, as their math appears solid from my quick review.  Let other geeks, engineers, and data obsessed chime in...  I have done all I can do.


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## DamienBricka (Feb 20, 2014)

Defiant said:


> The downside of OAK is pulling moisture from the outside through your stove



The winter outside air is dry so you are not pulling humidity in the stove or the house


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## Harvey Schneider (Feb 20, 2014)

DamienBricka said:


> The winter outside air is dry so you are not pulling humidity in the stove or the house


Not really accurate. Winter air can be saturated with moisture. It is just that saturated cold air holds a lot less moisture than warm air. The air only becomes dry when you heat it and its capacity to hold moisture increases. Defiant was incorrect, but so are you.
Don't feel that I am picking on you. Few people understand the concept of relative humidity and I just don't want misconceptions to become the accepted belief. It's the Engineer in me.
Read my post above.


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## DamienBricka (Feb 20, 2014)

Harvey Schneider said:


> Not really accurate. Winter air can be saturated with moisture. It is just that saturated cold air holds a lot less moisture than warm air. The air only becomes dry when you heat it and its capacity to hold moisture increases. Defiant was incorrect, but so are you.
> Don't feel that I am picking on you. Few people understand the concept of relative humidity and I just don't want misconceptions to become the accepted belief. It's the Engineer in me.
> Read my post above.



I agree with you I guess I did not explain myself correctly.


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## bondo (Feb 20, 2014)

Ok I am new to pellet stoves so I have a right to ask stupid questions.  When you say a combustion fan pulls 80 cfm would that be with the damper wide open? For example my damper is only open about 1/2" so am I pulling in 80 cfm of air or 20 for example?


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## Mt Bob (Feb 20, 2014)

Blowers are generally measured "free air",in their housing,no inlet or outlet restrictions.A stove has channels,bends,turns,damper adjustment,so realisticly the blower rating is not what is going through the stove.


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## Harvey Schneider (Feb 20, 2014)

bondo said:


> Ok I am new to pellet stoves so I have a right to ask stupid questions.  When you say a combustion fan pulls 80 cfm would that be with the damper wide open? For example my damper is only open about 1/2" so am I pulling in 80 cfm of air or 20 for example?


With the damper partially closed the blower will move less air than when it is fully open. The relationship is not linear and half closed does not mean half as much air. 
There is no direct way to relate the position of the damper to the cfm moved by the blower. The usual way to find out the amount of air moved is to measure the velocity of the air in a duct of known cross section. If the linear feet per second is know and the cross section is known the volume is the product of the two.


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## tfdchief (Feb 20, 2014)

Sorry if I missed something because I did not read the entire thread.  I installed my first wood stove in 1982.  At the same time, I installed an 8 in make up air duct from the outside to the front of the wood stove insert, not directly connected, just a register grate in the floor in front of the insert.  Then in 2011 I installed a new stove in the kitchen.  Again, I did not direct connect an outside air but tapped into the 8 in outside air I already had and put a 4 in air opening below the new wood stove in the kitchen.  With that set up, I have never had any problem with negative air.  Even with exhaust blowers in the house going like bathrooms and kitchen blowers.  Wood stoves use air from the house and need make up air.  Lots of ways to do it,  This just worked for me.


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## bondo (Feb 21, 2014)

Harvey Schneider said:


> With the damper partially closed the blower will move less air than when it is fully open. The relationship is not linear and half closed does not mean half as much air.
> There is no direct way to relate the position of the damper to the cfm moved by the blower. The usual way to find out the amount of air moved is to measure the velocity of the air in a duct of known cross section. If the linear feet per second is know and the cross section is known the volume is the product of the two.



Basically what I am saying is this. Earlier in this thread someone said the combustion fan moves 80cfm of air. What I am saying is if it where taking air from only a 1/2" gap instead of the whole 2" then isn't it taking in less air? So with that the equation made earlier about the volume of air sucked out of the house per hour would be different. Am I correct or way off? I am thinking of it like a bath exhaust fan for example. If it is 10" square but I block off 8" of it I isn't moving as much air out of the house. Just like the combustion fan wouldn't be taking as much air out of the house.


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## Pellet-King (Feb 21, 2014)

OAK This!


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## Harvey Schneider (Feb 21, 2014)

bondo said:


> Basically what I am saying is this. Earlier in this thread someone said the combustion fan moves 80cfm of air. What I am saying is if it where taking air from only a 1/2" gap instead of the whole 2" then isn't it taking in less air? So with that the equation made earlier about the volume of air sucked out of the house per hour would be different. Am I correct or way off? I am thinking of it like a bath exhaust fan for example. If it is 10" square but I block off 8" of it I isn't moving as much air out of the house. Just like the combustion fan wouldn't be taking as much air out of the house.


You are correct, the blower will move less air when the damper restricts it. What I was trying to point out is that it is not a direct correlation ie. 1/4 the opening does not mean 1/4 the air moved. How much less air is moved is hard to say.
Even without a damper, the path through the stove is reducing the volume of air the blower will move compared to the label plate number.


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## bondo (Feb 21, 2014)

Harvey Schneider said:


> You are correct, the blower will move less air when the damper restricts it. What I was trying to point out is that it is not a direct correlation ie. 1/4 the opening does not mean 1/4 the air moved. How much less air is moved is hard to say.
> Even without a damper, the path through the stove is reducing the volume of air the blower will move compared to the label plate number.



Thank you for helping me on that. I am just curious if it is worth an oak or not. If I have a 2" hole and only have the damper out a 1/2" that in the grand scheme of things isn't really that much volume of air moved. Even though I have decent insulation and new windows there is still some leakage around windows, doors, walls, ceilings, etc.... I mean was house was built in 1900.  If I put a hole in my wall that will add additional leakage around the pipe, not a lot but some. Then if the stove is off it will add even more. Add to that I have to put my oak to the north or west. I would cap it but wonder if wind could still affect me. I am not arguing for or against an oak I am just thinking out loud trying to decide. Everyone seems to be either you must do it or it is dumb. I am just really trying to think it out.


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## Harvey Schneider (Feb 21, 2014)

bondo said:


> Thank you for helping me on that. I am just curious if it is worth an oak or not. If I have a 2" hole and only have the damper out a 1/2" that in the grand scheme of things isn't really that much volume of air moved. Even though I have decent insulation and new windows there is still some leakage around windows, doors, walls, ceilings, etc.... I mean was house was built in 1900.  If I put a hole in my wall that will add additional leakage around the pipe, not a lot but some. Then if the stove is off it will add even more. Add to that I have to put my oak to the north or west. I would cap it but wonder if wind could still affect me. I am not arguing for or against an oak I am just thinking out loud trying to decide. Everyone seems to be either you must do it or it is dumb. I am just really trying to think it out.


Another valid reason for an OAK is to prevent a backflow of smoke when there is a power failure. 
If you have a rise in your vent, this might not be an issue. Power failure *and/or* a strong wind against the side of the house that has the vent can result in air traveling backwards through the stove and combustion products being released in the house.
Somebody else on the forum commented that they had to shut down their stove due to strong winds driving air back through their stove. That wasn't even concurrent with a power failure. Wind pressure was enough to overcome the combustion blower.
Both my stoves have a significant rise in the vent and I don't believe that backflow would be an issue. For the price of an OAK I got peace of mind and eliminated the forced heat loss. Seems like a simple decision to me. It's just the right thing to do.
You can probably tell from this that I am a very conservative Engineer. If something can go wrong, it should be prevented.


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## bondo (Feb 21, 2014)

Harvey Schneider said:


> Another valid reason for an OAK is to prevent a backflow of smoke when there is a power failure.
> If you have a rise in your vent, this might not be an issue. Power failure *and/or* a strong wind against the side of the house that has the vent can result in air traveling backwards through the stove and combustion products being released in the house.
> Somebody else on the forum commented that they had to shut down their stove due to strong winds driving air back through their stove. That wasn't even concurrent with a power failure. Wind pressure was enough to overcome the combustion blower.
> Both my stoves have a significant rise in the vent and I don't believe that backflow would be an issue. For the price of an OAK I got peace of mind and eliminated the forced heat loss. Seems like a simple decision to me. It's just the right thing to do.
> You can probably tell from this that I am a very conservative Engineer. If something can go wrong, it should be prevented.



I have a 5 foot rise and tested it by unplugging it. No smoke entered the house. Then the breaker popped a few days later after it got overloaded and again no smoke. I feel pretty good on that front. I could see if the wind was just right though it could give me a problem.


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## Polar Bear (Feb 21, 2014)

BrotherBart said:


> Besides the long established fact that cooler, denser air makes for more complete combustion:
> 
> http://chimneysweeponline.com/hooa.htm
> 
> Wood stoves should have'em too. Wish I had the guts to bore the hole in the back of my fireplace.



Some do. My father has an outside air kit for his woodstove. Burns amazing while only needing a QUICK clean in the spring.

Although it is the only one I've seen with one. Unsure why that is.


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## jlupi (Feb 21, 2014)

Defiant said:


> My indoor humidity runs a consistent 30+%, you should be familiar with CT weather, last week during all that rain outside relative humidity was 98+%.




the reason it is 30 is its RELATIVE HUMIDITY as in relative to temperature.  the humidity drops because you heated the air (it has the same amount of moisture in it).  If anything breathing cooking showering etc adds moisture to the air.


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## Mt Bob (Feb 21, 2014)

Just to throw another iron in the fire,if you live where you get fairly constant wind from a certain direction,and you put an OAK on the lee side of the house,you can drasticly reduce the stoves efficiency,lower output.OAK may not be for everyone.


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## bondo (Feb 22, 2014)

Call me stubborn but I haven't seen anything yet to justify a hole in my house. I have the oak it came with the stove. I have holesaws and every other tool needed. I even have a spot marked. It would take only a few minutes to do it but the question is still is it worth it. The equations don't tell me anything. 80 cfm through a straw or through firehouse is much different. Yes there is a point to be made about recycling air that has been already heated. However a new hole through a house is going to cause additional cold air a spot to come through. How much condensation does it cause? Hot air and cold air cause condensation. If it is snowing or raining and I am sucking that air in does that cause additional problems? I did a scientific test.  I held a piece of paper to my intake it had just enough suction to hold it there. I then went to my bathroom and held it to that exhaust fan. It sucked the paper in from about 2" away. The bathroom fan which is 70cfm is sucking a lot more then the stove is. I am not for or against an oak. I just have not seen anything that tells me it is a must or must not have yet.


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## Luvmesomesamples (Feb 22, 2014)

Does anyone know if my 2012 Harman accentra insert has separate intakes for the combustion and distribution air? I am considering adding an oak but don't want by distribution air to be cold, but wouldn't mind my combustion air to me. Thanks!


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## SwineFlue (Feb 22, 2014)

bondo said:


> Call me stubborn but I haven't seen anything yet to justify a hole in my house. I have the oak it came with the stove. I have holesaws and every other tool needed. I even have a spot marked. It would take only a few minutes to do it but the question is still is it worth it. The equations don't tell me anything. 80 cfm through a straw or through firehouse is much different. Yes there is a point to be made about recycling air that has been already heated. However a new hole through a house is going to cause additional cold air a spot to come through. How much condensation does it cause? Hot air and cold air cause condensation. If it is snowing or raining and I am sucking that air in does that cause additional problems? I did a scientific test.  I held a piece of paper to my intake it had just enough suction to hold it there. I then went to my bathroom and held it to that exhaust fan. It sucked the paper in from about 2" away. The bathroom fan which is 70cfm is sucking a lot more then the stove is. I am not for or against an oak. I just have not seen anything that tells me it is a must or must not have yet.



While there are definitely benefits to an OAK, the 80cfm intake number is pure fiction.  In reality it's closer to 8.  The 80 came from the rating of an exhaust blower, not an air intake.   Most of what comes out the exhaust is the combustion gases (ie the burnt pellets); the air pulled in is far less.  

That's why your bathroom fan is pulling more air than your stove.


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## iceguy4 (Feb 22, 2014)

Well I just spent the last hour reading this entire thread...and indeed real good stuff.     REAL GOOD STUFF  some exceptional posts about the attributes  of an OAK.
   I have  quoted some posts that I feel MUST tilt you toward an OAK....if you will keep an open mind.   the safety factor alone .     



bondo said:


> I could see if the wind was just right though it could give me a problem


   This poster said 2 times his chimney rise compensated for his fan....then says this...are you willing to take the chance??




Harvey Schneider said:


> Somebody else on the forum commented that they had to shut down their stove due to strong winds driving air back through their stove. That wasn't even concurrent with a power failure. Wind pressure was enough to overcome the combustion blower.


   I read this thread...his problem was attributed to no OAK   (stove is not affected when OAK and exhaust in close proximity)




Harvey Schneider said:


> Another valid reason for an OAK is to prevent a backflow of smoke when there is a power failure.


  Bingo 



Greenhorne said:


> I understand your position completely however is it your contention that with an OAK installed vs the same situation with no OAK that a substantial volume of already heated air is conserved to the point that the continual loss of air/heat through convection is marginalized so much that the OAK is compensating enough so that the normal heat/air loss is is surpassed and makes the modification justifiable or is it insignificant unless you have a really tight home? That is where I am going with this.



Can anyone help me with this?

what I learned from this thread...relative humidity .  having an  OAK    yes yes ...because its a no brainer.


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## iceguy4 (Feb 22, 2014)

Madcodger said:


> So there, knock yourself out.  Calculate for yourself.  And thank the people at Lincoln Electric.  I think I may go take up welding or something


   excellent post.   the calculator puts me @  $216/yr    VERY believable.


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## iceguy4 (Feb 22, 2014)

SwineFlue said:


> the 80cfm intake number is pure fiction.  In reality it's closer to 8.


 I have a boiler and I believe I'm WAY closer to 80 cfm (size of a phone booth) ...I'll grant on a pellet stove with a "no load" rating of 80 cfm will not flow that when used in a stove....I'd  estimate 60 though...  No flame intended...


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## SwineFlue (Feb 22, 2014)

iceguy4 said:


> I have a boiler and I believe I'm WAY closer to 80 cfm (size of a phone booth) ...I'll grant on a pellet stove with a "no load" rating of 80 cfm will not flow that when used in a stove....I'd  estimate 60 though...  No flame intended...


None taken!  But that's still exhaust flow.   What I'm saying is that intake airflow is not equal to exhaust flow.

80 cfm of combustion air would support around a half-million BTU/hr.   Pellet stoves run leaner than stochiometric, but not by a factor of 10.


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## Defiant (Feb 22, 2014)

You guys made a believer out of me, have the kit for my stove might be putting it in for next season. I guess some of the "know it all" personalities rubbed me the wrong way


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## iceguy4 (Feb 22, 2014)

SwineFlue said:


> What I'm saying is that intake airflow is not equal to exhaust flow.


  Yes, I know combustion increases exhaust flow over intake flow.  I kinda going by what I "feel" on the intake outside.  My airflow is significant . BUT I have a boiler capable of twice the BTU's of most stoves.   I haven't spent more then 1/2 an hour in the presence of a running pellet stove.


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## iceguy4 (Feb 22, 2014)

Defiant said:


> might be putting it in for next season


   Impressive.....BUT    You know the rules..."no pic's...it didn't happen"   LOL


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## tfdchief (Feb 22, 2014)

Well, just throwing my 2 cents worth in here.  I have 2 stoves.....see my signature.  Way back in the 80's I piped in outside air to a register in front of my Buck insert.....no OAK connection then.  When I put in my new EPA Hampton, of course it had the capability to connect an OAK.  I didn't.  Instead, I put a small air register, 4 in round, in the floor just under the back of the stove where combustion air enters, connected to the same 8 in outside air intake going to my Buck.  In both locations it of course introduces outside air that is cold, but with these outside air make up registers, I never have a problem with kitchen, bath exhaust causing problems with my stoves, except when the wife gets all 3 of them going at once  , and then sometimes.  Both registers can be closed.  It has worked well for me.


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## iceguy4 (Feb 22, 2014)

tfdchief said:


> Way back in the 80's I piped in outside air to a register in front of my Buck insert.....no OAK connection then.



Sounds like you were WAY ahead of your time!! !  although your system works it doesn't address risks due to a forced exhaust system in a power failure.


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## tfdchief (Feb 22, 2014)

iceguy4 said:


> forced exhaust system in a power failure.


  Sorry, but I don't understand that.  We have had many power failures in my 40 years of burning and never had any problems.  What is a "forced exhaust system"?  and how does a power failure play into it?


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## BrotherBart (Feb 22, 2014)

Pellet stove Chief. Intake air and exhaust are driven by a combustion blower. Not natural draft. No electricity. No intake and no exhaust. Like switching your car off.


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## tfdchief (Feb 22, 2014)

BrotherBart said:


> Pellet stove Chief. Intake air and exhaust are driven by a combustion blower. Not natural draft. No electricity. No intake and no exhaust. Like switching your car off.


OK, I guess I didn't read enough of the thread.


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## BrotherBart (Feb 22, 2014)

It has gotten derailed with the entrance of boiler talk. Iced as it were.


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## iceguy4 (Feb 22, 2014)

BrotherBart said:


> Like switching your car off.


Exactly BB ...But I'm not sure if chief has a pellet rig and understands the air intake can "belch" smoke  out  in such a situation..  something a "natural draft" wood stove  would almost NEVER do.


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## tfdchief (Feb 22, 2014)

iceguy4 said:


> Exactly BB ...But I'm not sure if chief has a pellet rig and understands the air intake can "belch" smoke  out  in such a situation..  something a "natural draft" wood stove  would almost NEVER do.


Nope, no pellet stoves.  Sorry I didn't read enough of the thread to know what I was talking about.  My apologies.


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## Realtor (Feb 24, 2014)

Here's my 'back of the envelope' analysis.  
Disclaimer;  This is from a newb who just cracked open his 4th ton of pellets.  I am waiting for the roof to clear so that I can install an OAK.
Pellet stoves use a fair amount of air for combustion.  Those figures run up to 80cfm.  Take whatever number you think is right.  For the sake of this argument I'll use 25cfm.  In a 24 hour period the stove will use 36,000 cubic feet of air.  My house is 3200 square feet.  I'm going to use an average ceiling height of 10'.  That would mean my house is aprox. 32,000 cubic feet.
If my stove is using 36,000 cubic feet of air every 24 hours that would mean that it is emptying the house 1.1 times per day.   Lets round that to 1 and say that once per day the air in my house is being replaced with cold outside air. ( I realize this is not 100% true because the air mixes  but for this calculation lets ignore that)
Lets say its 70 degrees inside my house and its 20 outside.  If I turned the air over in the house without running the stove the temperature in the house would drop to 20 degrees.  Virtually the same as the outside temperature.   On average that drop is about 2 degrees per hour.  I have no idea how much impact that will have on our stoves but clearly it will have some impact.  No?    


Hampton GCI60,   3 tons of Granules LG down and 3 tons of Cleanfire Pacific to go.


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## Harvey Schneider (Feb 24, 2014)

Realtor said:


> If my stove is using 36,000 cubic feet of air every 24 hours that would mean that it is emptying the house 1.1 times per day. Lets round that to 1 and say that once per day the air in my house is being replaced with cold outside air. ( I realize this is not 100% true because the air mixes but for this calculation lets ignore that)
> Lets say its 70 degrees inside my house and its 20 outside. If I turned the air over in the house without running the stove the temperature in the house would drop to 20 degrees. Virtually the same as the outside temperature. On average that drop is about 2 degrees per hour. I have no idea how much impact that will have on our stoves but clearly it will have some impact. No?



You're on the right track. Let me do the math for you.

Facts:
 temperature _________50______________________ 70 inside, 20 outside; = 50
Volume________________36000 cu ft/day_______________25 cfm on 24 hours/day (it is likely that the combustion blower is only running part of the time. See below)
Density of air at STP______0.07967 pounds per cubic foot___The number of pounds of air in one cubic foot at standard temperature and pressure
Specific heat of air at STP__0.24 BTU/lb/degree F__________The amount of heat needed to raise one pound of air by one degree F at standard temperature and pressure

Math:
Volume x Density x Specific heat x temperature  =  36,000 x 0.07967 x 0.24 x 50 = 34,417 BTU/day

34,417 (BTU/day) / 8300 (BTU/lb) / 76% efficiency = 5.456 lbs/day of pellets

Conclusion:
That comes to 0.136 bags of pellets a day to reheat the air that is wasted without an OAK
Even with cheap pellets that's about $0.60/day or $18/month
It gets worse with colder outside temperatures.
If for instance it was 5 outside, the cost becomes $0.773/day

If your stove's combustion blower is not on 24 hours a day, the cost will be proportionately less. If it is on 20% of the time the cost would be $3.60/month in pellets.


For those who don't want an OAK, it's your choice. Do as you please.


Edit:
Did some formatting because the spaces were removed by the forum software
Edit
Corrected math, off by a factor of 10


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## Polar Bear (Feb 24, 2014)

My owner's manual tells me the OAK is mandatory. Made my decision easy


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## DamienBricka (Feb 24, 2014)

Harvey Schneider said:


> Volume x Density x Specific heat x temperature = 36,000 x 0.07967 x 0.24 x 50



You should recheck your math I can up with 34,417.4 BTU/ day not
344,174 BTU/day


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## Harvey Schneider (Feb 24, 2014)

DamienBricka said:


> You should recheck your math I can up with 34,417.4 BTU/ day not
> 344,174 BTU/day


Your right I used 0.7967 instead of 0.07967. Will edit


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## DamienBricka (Feb 24, 2014)

Harvey Schneider said:


> Your right I used 0.7967 instead of 0.07967. Will edit



Regardless it is an additional $18 a month in one pocket. I would rather keep it for myself then give that money to someone else.


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## wsar10 (Feb 24, 2014)

Anybody care to touch on OAK placement..... (outside location vs exhaust)
and termination types or filters ???


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## SwineFlue (Feb 24, 2014)

wsar10 said:


> Anybody care to touch on OAK placement..... (outside location vs exhaust)
> and termination types or filters ???



To keep the wind from causing problems, it's best for the OAK to go through the same wall (or the roof) as your exhaust.  Keep the OAK below the  exhaust vent termination, but above any snow drifts.


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## wsar10 (Feb 24, 2014)

SwineFlue said:


> To keep the wind from causing problems, it's best for the OAK to go through the same wall (or the roof) as your exhaust.  Keep the OAK below the  exhaust vent termination, but above any snow drifts.


 
So the theory is hot air rises, which will keep the exhaust (gases) above the OAK ?


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## rwreuter (Feb 24, 2014)

How about this question.

I want to do and OAK....use double walled galvanized steel and place it vertically in the wall and then go out the rim joist.  Anyone see a problem with that?


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## Harvey Schneider (Feb 24, 2014)

rwreuter said:


> How about this question.
> 
> I want to do and OAK....use double walled galvanized steel and place it vertically in the wall and then go out the rim joist.  Anyone see a problem with that?


That would require that the rim insulation (if you have any) be compromised. It may result in a cold spot where the ceiling meets the wall.
How is that better than just going out through the wall?


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## rwreuter (Feb 24, 2014)

Harvey Schneider said:


> That would require that the rim insulation (if you have any) be compromised. It may result in a cold spot where the ceiling meets the wall.
> How is that better than just going out through the wall?



the wall is below grade and is 8" thick of concrete......

i don't think it can be any worse than the vent or the exhaust going out the rim joist.

i am just wondering it will be safe?


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## SwineFlue (Feb 24, 2014)

wsar10 said:


> So the theory is hot air rises, which will keep the exhaust (gases) above the OAK ?


Yes.  And keeping OAK & vent on the same side of the house will effectively cancel any wind that might blow into the exhaust.


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## Harvey Schneider (Feb 24, 2014)

rwreuter said:


> the wall is below grade and is 8" thick of concrete......
> 
> i don't think it can be any worse than the vent or the exhaust going out the rim joist.
> 
> i am just wondering it will be safe?


If the OAK is exiting the rim joist, you will have to bring it above the high snow level. Otherwise it should work. Just watch the equivalent length. Excessive length adds resistance to air flow.
When I installed my PDVC in the basement I went out through the concrete wall because I couldn't figure out how to clear the first joist. That necessitated an exterior rise. The exterior rise meant having two elbows outside. I used a 4" flexible aluminum duct inside so that I wouldn't have to worry about air restriction.


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## Charlie0664 (Feb 25, 2014)

Just out of curiosity, what has everyone been doing when using there dryer with these air tight homes (opening a window maybe)? Why is there no way for an OAK on a dryer (a dryer pulls a lot of air)?


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## Monica in France (Feb 25, 2014)

Reading this post I well understand the frustration of that "madcodger" .

But then I can't cook either.


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## dave2112 (Feb 26, 2014)

If you want to be a pellet master, you must put in an OAK.


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## Harvey Schneider (Feb 26, 2014)

dave2112 said:


> If you want to be a pellet master, you must put in an OAK.


That would be Pellet Meister, wouldn't it?
Your idea, you choose.


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## Snowy Rivers (Feb 26, 2014)

We have an air vent in the main air handler that brings fresh air in from the roof.

I have not used the Oaks on any of the three stoves.

We don't get any stale odors in the house from cooking or ???? that I have seen with many homes that are tight.

Fresh air is healthy, this said, if it was -30F outside, I might want to limit the amount of it though.

I would say this, if your house is sealed up tight, by all means install the Oak, as the stove will perform better.

Working the stove against a slight negative pressure inside is bound to have undesirable effects.

Snowy


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## bondo (Feb 26, 2014)

The equations and calculator on here basically do no good because we don't know the number to put in. Take my stove for example. The cfm that it can move is when it is sitting on a bench. The rating is at the end of the assembly. My stove has a manual adjustment and my fan is running at about half. Then the air it is sucking has to come through a tube then through the inside of the stove and out the vent. Now add to that I have my damper open about a half inch if that. What is my cfm? It is unknown but I would lean more towards the 8 someone mentioned then the 25, 40, or 80 that has been brought up so far. Like I said I am not for or against an oak. I am new to pellet stoves and have a lot of questions before I pop a hole in my wall. Does moisture cause issues? If I am bringing air in that is -10 instead of the room temp air it is using now does that have an effect? Does the stove cool down using air that is 80 degrees cooler?


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## Realtor (Feb 26, 2014)

Even at 8 cfm you're talking close to 12,000 cf per day.  That's about 1/3 the volume of the house I used in my crude calculations.  I think the problem is that we are talking about air infiltration that isnt  noticesble because its so spread out.  Imagine a hole in the wall of your house bringing in air at the rate of 8cfm.


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## razerface (Feb 26, 2014)

bondo said:


> If I am bringing air in that is -10 instead of the room temp air it is using now does that have an effect? Does the stove cool down using air that is 80 degrees cooler?


If you do not want to put that cold air into the stove,,,just lay it on the floor instead of hooking to the stove. Let the stove pull room temp air in. The object is to not create a vacuum ,,,does not have to feed directly into the stove


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## bondo (Feb 26, 2014)

Realtor said:


> Even at 8 cfm you're talking close to 12,000 cf per day.  That's about 1/3 the volume of the house I used in my crude calculations.  I think the problem is that we are talking about air infiltration that isnt  noticesble because its so spread out.  Imagine a hole in the wall of your house bringing in air at the rate of 8cfm.


True but there are natural air leaks in every house. I am not saying that air is not pulled in and needs to be replenished in some way. I am just curious about the other questions also to see the whole picture. Everyone wants to show me equations which is fine but what about the other questions also. If I put a 2" hole in my wall that will also allow new air to come in.


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## bondo (Feb 26, 2014)

razerface said:


> If you do not want to put that cold air into the stove,,,just lay it on the floor instead of hooking to the stove. Let the stove pull room temp air in. The object is to not create a vacuum ,,,does not have to feed directly into the stove


Hmmmmm never really thought about that method. Is that something you are doing?


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## razerface (Feb 26, 2014)

bondo said:


> Hmmmmm never really thought about that method. Is that something you are doing?


Yes, my oak lays on the floor beside the stove. It is easy to plug it when stove is not being used to keep cold air out too.


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## Harvey Schneider (Feb 26, 2014)

razerface said:


> If you do not want to put that cold air into the stove,,,just lay it on the floor instead of hooking to the stove. Let the stove pull room temp air in. The object is to not create a vacuum ,,,does not have to feed directly into the stove


My MVAE  was originally done that way. It worked well except when the wind blew against that side of my house. Then a cold draft flowed across the floor. As a result I close coupled the OAK to the stove. It might work well in a less windy location, but didn't work for my location.


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## Mt Bob (Feb 26, 2014)

chickenman said:


> On the multi-fuel stoves we sell we have a balanced air intake that runs in down the outer flue pipe with the exhaust running out through the inner flue.  Pellets are an easy burn but other biomass need this warmed induction air to run effectively.  In lab standard testing we achieved an efficiency increase from 88-95% so there is no question that a heat extracting Oak kit works.  The trick is to not reduce the exhaust temp below condensing point but this is pretty easy to work out.  In really cold climes, like all of you guys I guess, it can make the stove a bit harder to start but from there it is all upside.  Below is a pic of a standard horizontal flue kit.
> View attachment 128513


 Looks just like a standard direct vent gas heater setup.Selkirk makes a nifty setup for pellet stoves.I have wondered-yours and selkirks intake is very close together,but most stove mfg's specify a distance between them,usually 4 foot,except in vertical installs.Does this make yours and theirs illegal?Food for thought.Bob


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## Mt Bob (Feb 27, 2014)

chickenman said:


> You need to remember Bob that many recommendations are made without much reference to reason.  Our set ups are fully certified in Australia but I cannot speak for the US obviously.  Selkirk is not a fly by night operator so I expect it is fine but don't take my word for it.  We increase the intake - exhaust distances depending on the amount of air circulation and type of fuel if necessary as well.


Will post a new thread about legallity.This ought to be good!Have a good day.


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## Mt Bob (Feb 27, 2014)

Beating a dead horse,here.Look at past threads,warmer air burns more effecient.Stop comparing stoves to auto engines esp. turbo or blower fed.Both are combustion,one slower and not contained.Stoves are not pressure fed air(they tried it,did not work well).Ever wonder why fire fighters pray for cool damp air?


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## razerface (Feb 27, 2014)

Harvey Schneider said:


> My MVAE  was originally done that way. It worked well except when the wind blew against that side of my house. Then a cold draft flowed across the floor. As a result I close coupled the OAK to the stove. It might work well in a less windy location, but didn't work for my location.



Do you think the amount of air going thru the OAK varies because of that wind?
I don't want to connect mine partially for that reason. I do not want the stove to get varied inputs of air due to changing conditions of wind outside. If it pulls from the room, it should be more constant.  I do however, lay the end of the OAK close to the stove so that the circuit of air is close to the intake instead of drafting across the floor as yours did.

My OAK comes out on a walkout basement exit, shielded from wind, but wind can go anywhere. I have never felt any "puffing" or change in velocity thru the OAK,,, but I do not hold my hand over it 24/7 either. I just decided it makes sense to let the stove pull the air it wants instead of the OAK determining what air it receives. I think the OAK will naturally replace whatever the stove sucks in and sends up the chim.

Another thought,, my house is 2 yrs old. Code required the OAK with any chimney installation,,, so it was not my choice to put it in,,,but I am happy with it. My house is sprayed foam insulation with fiberglass over that,,, tight, tight, tight.

Also, i have wood stove, not pellet, but some things still apply.


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## Harvey Schneider (Feb 27, 2014)

bondo said:


> The equations and calculator on here basically do no good because we don't know the number to put in. Take my stove for example. The cfm that it can move is when it is sitting on a bench. The rating is at the end of the assembly. My stove has a manual adjustment and my fan is running at about half. Then the air it is sucking has to come through a tube then through the inside of the stove and out the vent. Now add to that I have my damper open about a half inch if that. What is my cfm? It is unknown but I would lean more towards the 8 someone mentioned then the 25, 40, or 80 that has been brought up so far. Like I said I am not for or against an oak. I am new to pellet stoves and have a lot of questions before I pop a hole in my wall. Does moisture cause issues? If I am bringing air in that is -10 instead of the room temp air it is using now does that have an effect? Does the stove cool down using air that is 80 degrees cooler?


The cfm moved by the blower can be fairly accurately estimated if the static pressure is known. 
Below are some numbers for a 60cfm blower similar to that used by ESW:
60 CFM of air flow free air
47 CFM of air flow at 0.1" SP (H2O), 
42 CFM at 0.2", 
37 CFM at 0.3", 
33 CFM at 0.4", 
21 CFM at 0.5", 
 7 CFM at 0.6"

I believe most stoves run somewhere between 0.1 and 0.2" static pressure (somebody correct me if I am wrong on this). So for a typical stove running at full feed the volume is still fairly high, somewhere around 45 CFM. At reduced burn rates it will be somewhat lower. If you have access to some sort of manometer you can hook it to the vacuum switch port on the blower and get a reasonable idea of the throughput.
The SP measured may not represent the full backpressure the blower is seeing if you have an unusually restrictive vent system.


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## Harvey Schneider (Feb 27, 2014)

razerface said:


> Do you think the amount of air going thru the OAK varies because of that wind?


No, the problem with a vent into the house is that wind increases or decreases the outside pressure with respect to the house. That causes air to flow. 
If the OAK and vent of the stove are on the same side of the house they see the same wind pressure and the wind can't, therefore, drive air flow.


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## razerface (Feb 27, 2014)

Harvey Schneider said:


> If the OAK and vent of the stove are on the same side of the house they see the same wind pressure and the wind can't, therefore, drive air flow.


 yea, I forgot again that this is a pellet stove thread, sorry.


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## Mt Bob (Feb 27, 2014)

Harvey Schneider said:


> No, the problem with a vent into the house is that wind increases or decreases the outside pressure with respect to the house. That causes air to flow.
> If the OAK and vent of the stove are on the same side of the house they see the same wind pressure and the wind can't, therefore, drive air flow.


 Hey harvey,figured you would know-last time had side of stove off,measured intake air speed,measured inside diameter of pipe,came up with 34 cfm,stove running at 1/2 setting(50%). Sounds about right,doesn't it?Bob


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## Harvey Schneider (Feb 27, 2014)

bob bare said:


> Hey harvey,figured you would know-last time had side of stove off,measured intake air speed,measured inside diameter of pipe,came up with 34 cfm,stove running at 1/2 setting(50%). Sounds about right,doesn't it?Bob


I don't really know your stove, but they don't differ all that much. The number sounds within the realm of believable. For a blower running at full speed, I would expect something on the order of 75% of it's label. Volume drops off pretty fast as speed is reduced, but there is no reason to believe that the 50% setting is anywhere near 50% of the speed. It may have been designed in an unquantified way. You know, "that seems fast enough". That approach works for most things until people start asking questions.
If you measured velocity at the center of the pipe, your number will be just a little bit high.That is because what is called the boundary layer effectively reduces the diameter of the pipe. Air at the boundary between the air and the pipe is standing still and as you move away from the wall of the pipe air velocity increases.
Measuring near the boundary layer gives results that are near impossible to do anything with.
Out of curiosity, what is the label plate rating of the blower?
I'm sure that I just added as much confusion as information. Engineers tend to do that. Ask what time it is and you'll get a dissertation on clock making.


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## Mt Bob (Feb 27, 2014)

Only have about a 1" gap between end of air pipe and back of stove where oak hose adapter is welded on,slid in my skymate,averaged out readings(I know better,ASE master)but was just looking for ball park.No blower markings on these old austrian stoves,just motor info(ebm papst).Next time I have side off I will try at full speed.Thanks.Bob


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## wsar10 (Feb 27, 2014)

I have a thought or an addition for discussion.......
Let me draw you a mental picture, My house is essentially "L" shaped the bottom of the "L" has a basement under (concrete floors, stone wall UN-insulated ceiling or floor of "the first floor") under the latter part of the "L" which is under my kitchen is a crawl space. An opening roughly 3'X3' connects the two spaces.

This crawl space is 16'x16' stone walls no insulation with dirt floor, the center is a trench to crawl in that is probably 4ft deep (4ft from bottom of floor Joice to bottom of trench) and roughly 4ft wide, the remaining area in the crawl space is probably only 2ft from floor Joice to dirt. Most of my water lines are in this crawl space _(go figure !) _therefore when it is 0* outside I run my boiler once or twice a day to get some heat into the crawl space.

I am considering doing an OAK but pulling air from this space, its cold air and I think it would draw warm air from my basement into the space and maybe keep it a bit warmer....... than I do not have to worry about the thing sucking in my exhaust in the event of some type of wind situation or the wind taking from my OAK or excessive moisture from outside coming in .

any thoughts ??


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## NHcpa (Mar 2, 2014)

I am getting a Harman 52i insert for a central chimney.  the chimney guy just left and said I can't do an OAK because the piping to an outside wall was too long.  also indicated that I don't need a damper plate as the chimney will be capped/sealed and the pipe insulated.  Make sense?


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## bondo (Mar 2, 2014)

NHcpa said:


> I am getting a Harman 52i insert for a central chimney.  the chimney guy just left and said I can't do an OAK because the piping to an outside wall was too long.  also indicated that I don't need a damper plate as the chimney will be capped/sealed and the pipe insulated.  Make sense?


The damper plate that was in the chimney originally?


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## NHcpa (Mar 2, 2014)

bondo said:


> The damper plate that was in the chimney originally?


I have read that once the damper plate is removed, sheet metal is used to cover it and a whole cut in the center for the pipe to pass through... The chimney/installer guy said it wasn't necessary to sheet metal the damper as the chimney cap is sealed and insulated.  kind of make sense and will pass local code.


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## mikkeeh (Mar 2, 2014)

wsar10 said:


> I have a thought or an addition for discussion.......
> Let me draw you a mental picture, My house is essentially "L" shaped the bottom of the "L" has a basement under (concrete floors, stone wall UN-insulated ceiling or floor of "the first floor") under the latter part of the "L" which is under my kitchen is a crawl space. An opening roughly 3'X3' connects the two spaces.
> 
> This crawl space is 16'x16' stone walls no insulation with dirt floor, the center is a trench to crawl in that is probably 4ft deep (4ft from bottom of floor Joice to bottom of trench) and roughly 4ft wide, the remaining area in the crawl space is probably only 2ft from floor Joice to dirt. Most of my water lines are in this crawl space (go figure !) therefore when it is 0* outside I run my boiler once or twice a day to get some heat into the crawl space.
> ...


 
My thought is:  You're still using air from inside the house....and it has to be replaced by outside air filtering in thru cracks/crevises etc.   Sucking combustion air from the crawlspace still lowers the overall pressure of the house.  Outside air being higher pressure will find its way in via the path of least resistance,


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## NHcpa (Mar 2, 2014)

NHcpa said:


> I have read that once the damper plate is removed, sheet metal is used to cover it and a whole cut in the center for the pipe to pass through... The chimney/installer guy said it wasn't necessary to sheet metal the damper as the chimney cap is sealed and insulated.  kind of make sense and will pass local code.


Nevermind!  the stove dealer gave a great deal on stove, install and piping through chimney.  Non insulated pipe that is capped at the top and he will be using a blocker plate at the damper location.


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## barbedwiredave (Mar 3, 2014)

I have had my OAK hooked up for 2 years.  For the past year I have been trying to wrap my head around the idea.  My main question is the convection blower of my stove is pulling room air, therefore pulling cold air from the outside.  Since I'm sure the convection blower pulls a lot more CFM than the firebox it kinda makes me think what's the point. I do have a leaky set of french doors close to the stove so that make me rethink me needing it.  Oh well, I'll stop thinking now.


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## iceguy4 (Mar 3, 2014)

barbedwiredave said:


> My main question is the convection blower of my stove is pulling room air, therefore pulling cold air from the outside


   No... the convection blower only moves air in the room



barbedwiredave said:


> Since I'm sure the convection blower pulls a lot more CFM


 I'm sure it does pull more then the EXHAUST blower. the only blower that the OAK makes up air for


barbedwiredave said:


> Oh well, I'll stop thinking now.


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## hyfire (Mar 3, 2014)

Just a word of note the colder the air in the stove , the lower the flue temps coming out, so yes the hotter the air in the hotter the air out....more heat across the heat exchanger =more efficiency%  Even though colder air may  have a better combustion its effect is negligible on giving you more  heat output..The OAK is really more for safety so you dont overheat the stove, if the room temp gets too hot, and reduce negative pressure effects in tightly sealed homes.  My stove mixes room air with combustion air , so in fact some fresh air gets in the room and gets sucked in the convection blower as well.  Its nice to have a bit of fresh air coming in IMHO.


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## NHcpa (Mar 3, 2014)

barbedwiredave said:


> I have had my OAK hooked up for 2 years.  For the past year I have been trying to wrap my head around the idea.  My main question is the convection blower of my stove is pulling room air, therefore pulling cold air from the outside.  Since I'm sure the convection blower pulls a lot more CFM than the firebox it kinda makes me think what's the point. I do have a leaky set of french doors close to the stove so that make me rethink me needing it.  Oh well, I'll stop thinking now.


Ditto on the leaking French doors - 2 sets...


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## barbedwiredave (Mar 3, 2014)

iceguy4 said:


> No... the convection blower only moves air in the room



But to move the air it has to pull from somewhere. I know my house isn't air tight so I can only assume it will also be pulling cold air inside.


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## Harvey Schneider (Mar 3, 2014)

Another reason to use an OAK. The reduced pressure in the house, caused by using house air for combustion, increases the ingress of Radon.


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## Harvey Schneider (Mar 3, 2014)

barbedwiredave said:


> But to move the air it has to pull from somewhere. I know my house isn't air tight so I can only assume it will also be pulling cold air inside.


The convection blower recycles room air and does not take air from the OAK.
The combustion blower input is usually directly tied to the OAK so that it uses only outside air for combustion.


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## barbedwiredave (Mar 3, 2014)

Harvey Schneider said:


> The convection blower recycles room air and does not take air from the OAK.
> The combustion blower input is usually directly tied to the OAK so that it uses only outside air for combustion.



That makes perfect sense for a completely sealed area.  In a house with air leaks there is no way for the convection blower to differentiate between recycled room air or air from the outside.  So if I unhook my OAK it will be pulling the same room/outside air as my convection fan but at a lower rate, correct?


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## mikkeeh (Mar 3, 2014)

barbedwiredave said:


> But to move the air it has to pull from somewhere. I know my house isn't air tight so I can only assume it will also be pulling cold air inside.


 Its no different than sitting a box fan in your living room.  The circulation fan does just that....circulate.   No air leaves or enters your house.   Pressures don't change.     
The combustion fan......on the other hand....takes air from inside your house (without an OAK)....and sends it outside. Thus reducing the pressure inside your house.   Outside air being at a higher pressure...filters in wherever it can.  With an OAK..outside air goes directly into the stove...and out the exhaust.   Thus...no change in pressure and no "makeup" air is needed.


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## barbedwiredave (Mar 3, 2014)

Now I see and understand it a little more.  Thank you


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## iceguy4 (Mar 4, 2014)

mikkeeh said:


> Its no different than sitting a box fan in your living room.  The circulation fan does just that....circulate.   No air leaves or enters your house.   Pressures don't change.
> The combustion fan......on the other hand....takes air from inside your house (without an OAK)....and sends it outside. Thus reducing the pressure inside your house.   Outside air being at a higher pressure...filters in wherever it can.  With an OAK..outside air goes directly into the stove...and out the exhaust.   Thus...no change in pressure and no "makeup" air is needed.


 Thank you...I was getting frustrated


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## wsar10 (Mar 4, 2014)

Harvey Schneider said:


> Another reason to use an OAK. The reduced pressure in the house, caused by using house air for combustion, increases the ingress of Radon.


Radon is only an issue if ur ontop of a landfill or farm runoff.


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## Harvey Schneider (Mar 4, 2014)

barbedwiredave said:


> That makes perfect sense for a completely sealed area.  In a house with air leaks there is no way for the convection blower to differentiate between recycled room air or air from the outside.  So if I unhook my OAK it will be pulling the same room/outside air as my convection fan but at a lower rate, correct?


Yes, that is correct, but what is your point?


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## moey (Mar 4, 2014)

Harvey Schneider said:


> Another reason to use an OAK. The reduced pressure in the house, caused by using house air for combustion, increases the ingress of Radon.




Its much much easier to pull makeup air from your leaky windows and sill which would not have radon. The radon is coming from your below grade concrete seeping in slowly from the soil. But I guess it would come in a little more from the concrete walls.


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## weeks001 (Mar 4, 2014)

Can someone point me in the direction of an explaination of the OAK system? Who makes it, How it's installed, what units it works best on ect...?
Thanks


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## Harvey Schneider (Mar 4, 2014)

moey said:


> Its much much easier to pull makeup air from your leaky windows and sill which would not have radon. The radon is coming from your below grade concrete seeping in slowly from the soil. But I guess it would come in a little more from the concrete walls.


The air will come from wherever it wants to come from. If the pressure in the house is reduced, more radon will seep in through cracks and porosity of the basement. A house with positive pressure (near impossible to achive) would have very little elevation of Radon above the local normal levels outdoors.


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## mikkeeh (Mar 4, 2014)

weeks001 said:


> Can someone point me in the direction of an explaination of the OAK system? Who makes it, How it's installed, what units it works best on ect...?
> Thanks


 
Have you read this thread from the beginning???  The theory has been explained ad nauseam.


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## SwineFlue (Mar 4, 2014)

weeks001 said:


> Can someone point me in the direction of an explaination of the OAK system? Who makes it, How it's installed



It should be offered as an option (or may be required) with the stove and described in your manual.


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## trbinrat (Mar 4, 2014)

wsar10 said:


> Radon is only an issue if ur ontop of a landfill or farm runoff.



I think your a little miss informed on that one.


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## BrotherBart (Mar 4, 2014)

trbinrat said:


> I think your a little miss informed on that one.



For sure.


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## BrotherBart (Mar 4, 2014)

mikkeeh said:


> Have you read this thread from the beginning???  The theory has been explained ad nauseam.



In fact enough.

Closing it.


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