Why did you install an outdoor air kit?

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I just hope it is not cooling the exhaust gases to the point at creosote forms in the exhaust pipe.

Eric

Knowledge from the internet (which we know is where everything is true...)

Wikipedia "Creosote" page:

Burning wood and fossil fuels at low temperature causes incomplete combustion of the oils in the wood, which are off-gassed as volatiles in the smoke. As the smoke rises through the chimney it cools, causing water, carbon, and volatiles to condense on the interior surfaces of the chimney flue. The black oily residue that builds up is referred to as creosote, which is similar in composition to the commercial products by the same name, but with a higher content of carbon black.

73% of heating fires and 25% of all residential fires in the United States are caused by failure to clean out creosote buildup. Since 1990, creosote buildup has caused 75% fewer fires.[80] This is partly due to the use of efficient wood-burning stoves that fully combust the carbon from fuel, and partly due to the use of Class A flues, insulated double wall stainless steel pipe.

My understanding of modern pellet stoves is that they are efficient in their burning of the product...there should be less issues with creosote formation. Through reading posts on this and other forums it seems there are more issues with exhaust pipes being clogged up with ash, with the recommended remedy being the reverse leaf blower trick. The leaf blower does nothing to remove creosote.

Using the triple walled (?) pipe to integrate the intake with the exhaust will decrease the temperature of the exhaust...this could cause a problem with the natural draft of the exhaust in the event of a power outage, with no fan forcing the gasses out the vent

And, to further expound on creosote, I present to you "Mr. Creoste", from Monty Python's Meaning of Life. I apologize in advance...


 
I have a Lopi pioneer freestanding stove. Did not install OAK, on the advice of my chimney sweep who sold me the used stove. My house isn't that tight...and he said it does NOT matter.
 
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I have a Lopi pioneer freestanding stove. Did not install OAK, on the advice of my chimney sweep who sold me the used stove. My house isn't that tight...and he said it does NOT matter.

Clearly he is the smartest chimney sweep out there.
 
Clearly he is the smartest chimney sweep out there.
A real genius. Has a side business selling flat earth maps, 'cause everyone knows those science types are just crazy.
 
I'm surprised one of the over thinkers hasn't figured out how much energy is being lost using cold air to burn vs warm air to burn. Wait, someone apply for a government grant it study the issue it should be good for a few million$$
Would this be in opposition to the under thinkers? I think I know which camp I want to be in, but to each their own.
 
Yesterday I broke my A$$ boring not 1, but 2 holes through 12" concrete for my OAK. I seriously contemplated NOT doing the OAK, but I did a little experiment using my upstairs stove 1st. I disconnected the OAK upstairs and I noticed an immediate slight draft from the windows on either side. I reconnected and the draft was gone. Even though my owners manual for both stoves says it's mandatory for OAK I wanted to see for myself. It works for me even though the install downstairs was BRUTAL!!! This is a GREAT site.... Thanks for all the tips and advice!!!
 
Last weekend it was brutally cold here in the northeast, I ran my stove for the first time all winter burning leftover's, i'll tell you without OAK every draft made there presence , now today no stove burning, using oil and it's 32 degree's out and no drafts week later, my stove has a 2" pipe but there's a box with a circle hole which defeat's the connection if I wanted to connect a outside pipe, I guess I could use some metal duct tape and seal it, but i have a insert and the thought of drilling a 2" or bigger hole in my fireplace wall doesn't appeal to me., sure you could someday cement it off but that I would think would hurt resale value.
Or using the ash cleanout as OAK would just suck the same air from the house anyway
 
Last weekend it was brutally cold here in the northeast, I ran my stove for the first time all winter burning leftover's, i'll tell you without OAK every draft made there presence , now today no stove burning, using oil and it's 32 degree's out and no drafts week later, my stove has a 2" pipe but there's a box with a circle hole which defeat's the connection if I wanted to connect a outside pipe, I guess I could use some metal duct tape and seal it, but i have a insert and the thought of drilling a 2" or bigger hole in my fireplace wall doesn't appeal to me., sure you could someday cement it off but that I would think would hurt resale value.
Or using the ash cleanout as OAK would just suck the same air from the house anyway


Where does your oil burner get its combustion air supply from ?
 
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I just hope it is not cooling the exhaust gases to the point at creosote forms in the exhaust pipe.

Eric

No creosote whatsoever. Nice light, soft grey ash. One swipe with a soft bristle flue brush and I'm done. My flue is vertical and 22 feet tall. About 10 feet of the 22 feet is insulated with 1" ceramic batt insulation, partly because I wanted to make sure I didn't lose my natural draft. I do have plenty of natural draft even with the flue gas cooling. I have not stuck a thermocouple in the flue gas exit to see what the final flue gas temperature is, but, based on the condition of the ash at the top, I'm fine.
 
Would this be in opposition to the under thinkers? I think I know which camp I want to be in, but to each their own.

My dealer has sold coal, wood and pellet stove for over 30 years. They said an OAK was not needed for my 52i installed in a enter chimney fireplace. If only they were as smart and all-knowing as forum members here.
 
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Where does your oil burner get its combustion air supply from ?

My oil burner is located in the basement of the house, not in a regular living space. The foundation of my 100 house is made with locally sourced rock, cemented together. The sill rests on said foundation.

My basement is anything but airtight. The gas furnace (30+ years old as gas, a conversion from an oil burner that was installed over 45 years ago) and the gas water heater both have a vent to exhaust the offset, and the air is made up from within the basement area. The air is replaced from leaks in the foundation and attachment area of the house to the foundation. Yes, the basement is a bit drafty. As it should be, due to the age of the house and how was designed.

Houses are now designed with air makeup for combustion devices, preferring to use outside combustible air than interior. Partly due to the idea that a super insulated house is better than a standard insulated house.

Remember the radon scare? Certainly overblown, especially here in the NorthEast, but it made for some changes in building codes due to the issue.

High concentrations of radon in homes were discovered by chance in 1985 after the stringent radiation testing conducted at a nuclear power plant entrance revealed that Stanley Watras, an engineer entering the plant, was contaminated by radioactive substances.[71] Typical domestic exposures are of approximately 100 Bq/m3 (1.3 pCi/L) indoors. Some level of radon will be found in all buildings. Radon mostly enters a building directly from the soil through the lowest level in the building that is in contact with the ground. High levels of radon in the water supply can also increase indoor radon air levels. Typical entry points of radon into buildings are cracks in solid foundations, construction joints, cracks in walls, gaps in suspended floors, gaps around service pipes, cavities inside walls, and the water supply.[2] Radon concentrations in the same location may differ by a factor of two over a period of 1 hour. Also, the concentration in one room of a building may be significantly different from the concentration in an adjoining room.[3]

Now add a device (pellet, oil, gas) that needs to pull in an abundance of air for it's operation. That air, as we all will agree, needs to come from somewhere. Near the device in the basement (for those of us that have basements) that air getting to the device will be perceived as a draft....and that draft was seen as one of the ways excessive radon (in it's gas form) was entering homes.

I spent a few weeks going to at least 6 pellet stove dealers, its of questions, getting pries for the device, getting pricing for the installation. None of them recommended installing an OAK (this was when I contemplated dealer install). The one dealer that came to the house, upon seeing how the installation would proceed, agreed then that it would be smart n to put the OAK in (the install was through a plaster wall, wood shingle siding, and I was leaning towards the wall vent that would integrate both in one). The installation would be no more problem than one without an OAK. He did admit upon my questioning that using outside air would increase the economics of running the stove.

One Ravelli dealer told me that Ravelli does not recommend it, it screws up the combustion of the stove b constantly changing the temperature of the incoming air...it was better to use conditioned room air(?). Say what?

Another Ravelli dealer showed me the installation manual, showing the part where Ravelli recommends it, in print. But they said to leave it up to the installer for final word(?). Say what? Does each installer have full certifications? Theirs didn't...but they were their trusted installers. In our state the installers do not need to be licensed, or trained. The install does need to pass building code...even there you sometimes get the luck of the draw when the inspector arrives, some knowledgable, some not.

I installed the stove myself...saving well over $1000 in the process. Installation was trivial. Used all Harman components, including the combination intake / exhaust vent kit. Building inspector was impressed (even more impressed when I told him this Accentrs was a recently purchased used stove, 10 years from manufacturing).

Other friends and acquaintances that have seen the install, and see that it has the intake, and get an explanation of why it is there, wonder if installing one would cut down on the drafts in their house. Not all of them, but most of them.

Installing one finally made sense to me after calling a good friend that has had his own HVAC business for over 40 years...he does high end installs where quality of air matters for manufacturing processes and for health care related businesses. His recommendation for a pellet stove in a home? If it doesn't cause a huge amount of cash outlay, go for it. Otherwise be ready to accept an installation that is not as efficient.
 
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I'm always amazed by the replies to this question.
I get the impression that people have not actually sussed out what an OAK is.

You have a pellet stove to have that nice snug feeling.
Why ruin it with unnecessary drafts ?

On the economic side there is no argument at all. You are paying for all that hot air going up the chimney. Whether it is preheated in the house or whether it is coming in directly from the outside makes no difference at all . On the other hand if you pre-heat it in the chimney ( concentric tubes and all that) you can actually save a bit.

Worse than this is the quantity of water vapour going up the chimney – that costs you even more.
Has anyone designed a pellet stove with a condensation exchanger ?
 
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I'm always amazed by the replies to this question.
I get the impression that people have not actually sussed out what an OAK is.

You have a pellet stove to have that nice snug feeling.
Why ruin it with unnecessary drafts ?

On the economic side there is no argument at all. You are paying for all that hot air going up the chimney. Whether it is preheated in the house or whether it is coming in directly from the outside makes no difference at all . On the other hand if you pre-heat it in the chimney ( concentric tubes and all that) you can actually save a bit.

Worse than this is the quantity of water vapour going up the chimney – that costs you even more.
Has anyone designed a pellet stove with a condensation exchanger ?

France? You're in France?

Wicked cool...

Which area?
 
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My dealer has sold coal, wood and pellet stove for over 30 years. They said an OAK was not needed for my 52i installed in a enter chimney fireplace. If only they were as smart and all-knowing as forum members here.
Well, to be fair he said "not needed". Technically true. "Not needed" is not necessarily the same thing as "won't make a difference in comfort" :p.
 
Well, to be fair he said "not needed". Technically true. "Not needed" is not necessarily the same thing as "won't make a difference in comfort" :p.

Je m'en remets à ton votre jugement
 
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I'm surprised one of the over thinkers hasn't figured out how much energy is being lost using cold air to burn vs warm air to burn. Wait, someone apply for a government grant it study the issue it should be good for a few million$$
Didn't they already figure this out with Selkirk DT?
 
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My dealer has sold coal, wood and pellet stove for over 30 years. They said an OAK was not needed for my 52i installed in a enter chimney fireplace. If only they were as smart and all-knowing as forum members here.
Well, yes. IF only... Sadly, that appears to not be the case.

If only the people selling such things were required to understand the science behind them. If only the people buying them knew the same. Absent either, we have these debates.
 
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Lets do the oak math again...

A 100cfm combustion blower running 24 hours is 144,000 cubic feet of air, exiting the house.

A 1350 sq foot home, say 28x48, 7.5" ceilings, is 10,080 cubic feet.

So, without an oak, the pellet stove is turning the air over in the house 14 more additional times than it would naturally. Every day.

It appears any way one adjusts for their particulars, stove cfm, house volume, the bottom line is aiming fresh air at the stove combustion is an advantage.
 
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I don't question the math but have another math question. Has anyone measured how an OAK might negatively effect the circulation of warm air throughout a house? In my house, the upstairs bedroom and my office down the hall both average four degrees higher when the pellet stove is operating versus heating the same area in the main part of the stove via oil, both being set to 70 degrees. My thinking is as the stove pulls dense cold air to the stove, the draft all talk about, it has to be replaced by less dense warm air over the top, creating a convective current or loop. So I wonder, if the stove gets most of its combustion air from the outside via an OAK, it won't pull the cold air toward it, hence warmer air won't replace it and the rooms will be colder as a result.
 
I don't question the math but have another math question. Has anyone measured how an OAK might negatively effect the circulation of warm air throughout a house? In my house, the upstairs bedroom and my office down the hall both average four degrees higher when the pellet stove is operating versus heating the same area in the main part of the stove via oil, both being set to 70 degrees. My thinking is as the stove pulls dense cold air to the stove, the draft all talk about, it has to be replaced by less dense warm air over the top, creating a convective current or loop. So I wonder, if the stove gets most of its combustion air from the outside via an OAK, it won't pull the cold air toward it, hence warmer air won't replace it and the rooms will be colder as a result.
I think that's just a air circulation and insulation problem. If your oil burner was just in one room, a space heater, you would see the same results. The OAK doesn't cause circulation problems it cures them.
 
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