COLD AIR EXCHANGE EXPLANATION???

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. . . but wait! If I pull -20 degree air from my OAK into burn chamber, won't that cool down my fire? Won't my pellet stove not produce as much heat?

Well?

Well yes. But you'll still have a fire.

Fire good.

 
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The Nascar stuff, well, I don't know. I'm more of a SCCA guy myself.
Are you really from Massachusetts? That's so un-northeast...

redneck.jpg


Dan
 
. . . but wait! If I pull -20 degree air from my OAK into burn chamber, won't that cool down my fire? Won't my pellet stove not produce as much heat?

Well?

You'd prefer drawing -20 degree air into your house in the form of drafts to compensate for the vacuum created by your stove?
 
Harman manual: ". . . [the company] strongly recommends attaching outside air in all installations, especially lower level and main floor locations." [bolding is mine]


My manual strongly recommend a battery backup in case of a power failure. I think this will prevent smoke from entering the house due to negative draft as it will keep the stove running until it shuts down properly. OAK is not needed if installing into an existing chimney such as mine plus drawing air from the basement. By the way, I had a power outage and smoke did not fill my house as the backup battery kicked in and all was ok. All smoke went up the stack as advertised.

I'm not against OAK, I just don't think it's the answer to all our draft problems. If you have it fine, enjoy it, because I enjoy my stove without it.
 
My manual strongly recommend a battery backup in case of a power failure.

I'm hoping your manual also recommends putting the stove on a UPC / battery backup, to protect the controller.

I think this will prevent smoke from entering the house due to negative draft as it will keep the stove running until it shuts down properly.

Yes, correct. If the power goes out the battery backup kicks in. i.e. the power is not really "out", until the battery dies.

OAK is not needed if installing into an existing chimney such as mine plus drawing air from the basement.

Is the basement attached to the house? Do you have a way to access the basement from within the house? If so, the combustion air is coming from inside the house. Somehow the makeup air is reaching the stove...by way of a draft.

By the way, I had a power outage and smoke did not fill my house as the backup battery kicked in and all was ok. All smoke went up the stack as advertised.

As I think I stated before, if you have a sufficent stack height for your exhaust the majority of the smoke still in the stove during an outage ~should~ find it's way up there, the path of least resistance whether you have a battery backup or not.

I have a Harman Accentra-2 FS circa 2004. My good friend has a Harman Accentra FS circa 2006. I have an OAK, he does not. He is very jealous of the quality of my flame, of the fact that my glass front does not cloud up. And I tell him so every chance I get. My bet is that we'll be putting an OAK on his in the spring.

And heh...I said "quality of my flame". Do I sound like a wanker or what?
 
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Is the basement attached to the house? Do you have a way to access the basement from within the house? If so, the combustion air is coming from inside the house. Somehow the makeup air is reaching the stove...by way of a draft

Exactly. There are essentially two spaces in a house: Conditioned space, which INCLUDES EVERYTHING that is within the envelope of the house and subject to air movement within that envelope, and unconditioned space, such as an attic or, hopefully, the garage. Most basements are accessible from within the home via an unsealed, interior door and many have no insulation or air sealing between the basement and the first floor. They become, even if not intended, part of conditioned space.

A good general rule is to never draw air needed only for combustion from conditioned space. As I noted in an earlier post, doing so means that you are using conditioned air (i.e., air you already paid to heat) just to feed oxygen to a fire. Bad use of money, that will leave you less comfortable.

By the way, I've noticed that many forum members attempt to overcome poorly sealed and insulated homes by just burning more pellets. An alternative is to better air seal and insulate that conditioned space. That includes not using your stove as a vacuum pump that sucks out conditioned air, replacing it -unnecessarily - with cold air from the outside.

Oh, and one last thing - I continue to think the mods should create a sticky about OAKs, which is why I earlier joked about the number of new questions we get every year about this issue. I am not poking fun at new members. I'm calling out the fact that our mods almost certainly understand this issue and the science behind it (they certainly should, so I give benefit of doubt), and that it would actually help many visitors and new forum members gain access to much-desired information to have this topic as a sticky. It seems more efficient than multiple threads about the same issue, every year. But then again, it does give us all a reliable topic for generating posts.
 
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I just go back to previous OAK threads, copy my replies I posted there and paste them in new threads.
 
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Oh, and one last thing - I continue to think the mods should create a sticky about OAKs, which is why I earlier joked about the number of new questions we get every year about this issue.

While this is a good idea and will help somewhat, until the stove manufacturers themselves state in their instructions the an OAK is mandatory people are still going to try the cheapest way to set up the stove even though in the long run it will actually cost them more money burning more fuel and bringing in cold air. Just my thinking.
 
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until the stove manufacturers themselves state in their instructions the an OAK is mandatory

I have two stoves, each hooked up to OAK.
That said.
Truth is, it isn't "mandatory".
"Strongly suggested" or something similar, is more appropriate.
Which is what some say.
If a stove works equally well, either way, in a particular application,
the OAK is not going to increase the performance of the stove.
Their obligation is to make sure the stove runs as good as it can.
Not how well you heat your house.
That's why they will usually say "heats up to yada yada sq.ft."
It's a variable, not a constant.

Just my opinion.. Dan
 
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My manual strongly recommend a battery backup in case of a power failure. I think this will prevent smoke from entering the house due to negative draft as it will keep the stove running until it shuts down properly. OAK is not needed if installing into an existing chimney such as mine plus drawing air from the basement. By the way, I had a power outage and smoke did not fill my house as the backup battery kicked in and all was ok. All smoke went up the stack as advertised.

I'm not against OAK, I just don't think it's the answer to all our draft problems. If you have it fine, enjoy it, because I enjoy my stove without it.

I don't have OAKs for draft problems (the basement stove drafts wonderfully by the way - even before I installed the OAK two months after having the stove installed). Don't even need a battery back up for draft problems in the case of power outage, although I also use them. Just keeps the house from being drafty on the inside with air coming in from the outside. Don't know where you got the idea I was talking about exhaust drafting from - my earlier post (prior to the one you quoted) was all about my experience of cold air drafting into the house from the outside until I installed an OAK - didn't say anything about smoke issues.
 
Truth is, it isn't "mandatory"

Ya that's the truth and a problem. Over the years I've seen many a problem with stoves without OAK/FAK, never see one problem with one other than lack of maintenance and they get plugged up during the summer mostly.

If a stove works equally well, either way, in a particular application,
the OAK is not going to increase the performance of the stove.

It may work equally well or may not without an OAK. Seen many a problem with a stove that usually run ok and then someone turns on a vent fan in the bathroom and 20 minutes later the fire is out, that will NEVER happen with an OAK installed.
And while it may not increase the performance of the stove, it will improve the stoves ability to heat the house, less drafts means a warmer house, the two are not mutually exclusive so in a way it does increase the heating performance.

I could list many problems running a stove without an OAK but can only think of the little extra cost and a little maintenance as the only negatives with having an OAK.

How many people come here for troubleshooting? One of the first things is to find out if an OAK is installed. If not then the troubleshooting gets hazy until it can be ruled out being the problem.
 
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It may work equally well or may not without an OAK.
But that is my point, with regard to a manufacturer saying it is "mandatory"...

Dan
(keep in mind, "I" would always suggest it.
But I am not a manufacturer...) ;)
 
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Thanks, I need to create a new term for all of those OAK people out there. ::-)

Shouldn't it be " IAK ", not " IOK "?

Either one is OAKie dOAKie with me...
 
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My wife and I have a 24 year old pellet stove that gave up the ghost last week.
We are looking at new pellet stoves and have talked to (2) local dealers/installers.
Can some of the members here, please explain (in real simple terms),
what a "Cold Air Intake" on the new pellet stoves is and what it does?

I've hear talk like, "Negative Pressure", "depends on what type of house you have" ect.

We currently live in a single level Ranch House in California, that was built in 1974.
It has no basement, and I'm sure it does not have tight seals around the doors ect.
It has a fireplace that has been "bricked up/sealed", with a 3" diameter inlet, that our current pellet stove connects to.
I goes up into a regular chimney with no "center tube".
My F-I-L, says it should be alright as long as we clean the chimney every year.

So if a new pellet stove is cost prohibitive, a I buy a used one,
(or a less expensive one at Home Depot), and just vent it into the chimney, is that OK?

Now I assume that many installers may cringe at my question,
but we've been running my old "Jamestown J2000T" stove, like this for 3 years.

Any help, info, links would be appreciated.
I'm a beginner here, so the simpler.....the better.

I can add and suggest a direct vent product, combining the exhaust and OAK. I just re-vented my stove with a ventis direct vent pipe and it is absolutely fantastic. The main advantages: one pipe and one hole in the roof or wall. All incoming air is warmed by the exhaust so no reduction of efficiency on very cold nights. Disadvantage: Pipe is large (5 inches) and is harder to install.
 
Shoot a couple pictures. Only pipe we have seen with the feature I have seen is by Selkirk
 
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