What's the point?

We have a Enviro Mini, a PP130 which was removed from the basement and replaced with a Lopi Yankee PS that I just rebuilt, and yesterday finished the install. The PP130 is going to replace the oil blaster in the garage.

The PP130 has a OA pipe directly to the burnpot chamber from the outside air connection, which I ran it with very sucessfully.

The Enviro Mini, is nothing more than a short length of pipe that dumps out directly behind the back panel and is not connected to the burnpot chamber at all, so I didn't bother with the OA.

The Lopi has a pipe leading to the burnpot chamber, but there is a large rectangle hole in the side of it. Soooo.... I attached a piece of sheet metal over the hole with high temp rtv so it gets nothing but outside air, and yes I have a functioning CO detector.

What would the point be to connect OA to a stove that is not connected to the burnpot chamber? The way I see it, all it would accomplish would be putting a 2in hole in the wall.

I lit it yesterday for the first time in the house, after sealing and securing the chimney sections, and it has run for almost 24hr now as low as it will go, and it has kept the whole place a nice even temp.

The pellets we have are completely new to me, so the jury is still out on them.
The glass is a little dirty, but nothing you would not expect running a big stove low and slow for a long time. The burnpot is pretty clean and free of clinkers, unlike the PP130 which would be clogged and the glass totally black.

So anyway, looks pretty good so far and seems to be a worthwhile expenditure to upgrade from the PP130.

 

Perhaps because it was designed to burn better that way.But many have connected directly without issues.others add a valve to turn off when not using stove.Will leave you some reading info.
A non-commercial service in support of responsible home heating with wood - The Outdoor Air Myth Exposed

 

When I had my Astoria, I had brought up the same question on that other website, and the final consensus was that the hole in the side of the OA tube was to allow a mix of heated indoor air to mix with the outside (and possibly VERY cold) air. Personally, I didn't have any issue with all the air coming from the outside, cold or not, but others felt it should be closer to room temp. I never had any issues, and my Englander 10-cpm had a direct pipe to the combustion chamber, and again, no issues.

 

There is no other website.

 

Finally something in writing that is logical and makes sense. I have heard too much mouth noise from blowhard armchair experts before, that would just lose their minds if the subject was brought up.

The OA was put in in place for the other stove, and I did it because it was our first stove. I just went with it as that was what the "experienced" overlords said to do. I put a plate over the side opening on this stove to keep freezing cold from constantly coming in. I think I should just take the whole OA thing out and cap the hole.

 

Some of those guys can really get their knickers in a knot. They will argue anything to prove themselves superior. Don't forget about cold air being denser so there is more oxygen! Sheese...

 

I read that whole write-up too, and found it to be very informative. Initially it seemed to contradict what I have been told, however - as I read through it seems to me it was geared toward heating appliances that don't have a combustion fan. Wood stove, fireplace etc. - where not as much air is moving. With a pellet stove having a combustion fan, and the article "almost" touches on this, significantly more air would be going "up the flue" so to speak, and also the situation would be less susceptible to large draft changes, because you've got a fan helping to keep the air flow more constant. I think in that scenario, suspect there is more of a case to be made for drawing the combustion air from outside as opposed to pulling air from inside the house.

 

I also have a slim chance of back draft because the chimney goes up 4 feet from the stove, out another 3 feet to a T, then up another 12 feet .

 

Although an interesting article, it specifically says it is talking about fireplaces and woodstoves in the first sentence. Pellet stoves are a whole 'nother animal - especially if your house envelope is fairly tight. The exhaust fan for the pellet stove is the main concern as it actively pulls air out of the house. However, I really don't care if someone hooks up an OAK or not.

 

When we bought our P43 from Fallons I asked whether I needed to install an OA and they said they don't usually recommend using one.

sam

 

LOL! I threw that up just to see the reactions.No,I do not agree with all of it.Yes,my main stove has an OAK,but I have a valve on mine,2 reasons.when below -10,frost inside,and for wind blows on that side of the house.As far as air use,wood and pellet prob. the same,both stoves burning properly,as you cannot change the stoichiometric air to fuel ratio,and both units will waste air when starting and cooling down.Biggest thing is an OAK really knocks down drafts across your feet.As far as why some stoves are not direct to the fire pot,I have 2 guesses,1 was done that way for years on european stoves,to help change the air in the living space,and 2 perhaps because so many "sealed" hoses today,fire burning low,both bathrooms and kitchen exhaust fan on,and you could suck smoke into the house past the rope gaskets on the stove.IMHO sealed houses are not good for your health.OK ther is more stuff for you.

 

The local stove shops and installers I’ve talked to have downplayed the importance of an OAK as well. They tend to look at it from one point of view: is your house a brand new construction and insulated so tight that using inside air would starve the fire of oxygen? If you ask about general efficiency, and not pulling cold air into the cracks and crevices in the house, they look at you like you’re crazy.

 

yup......cold air is denser, and does carry more Oxygen......but to play the Devil's Advocate......what happens when your stove which uses room air has to fight the range hood, clothes dryer, furnace, bathroom fans, air exchangers, etc, all of which also draw room air out of the house envelope, given the fact that these days new homes are VERY tight with stretch codes, etc?

 

Smoke in the house happens.

 

I understand the physics involved with the temperature making the air denser, but I personally have not seen proof that it would help a small controlled burn like a pellet stove or wood stove. Unless of course you're running a compression ratio of 10-1 or more, or maybe a blower with high octane fuel? lol

 

As you all like to think,here is some more info. Another outside air intake,this one on a wood stove----
https://salamanderstoves.com/documents/cold-air-intake.pdf
and this,which pertains to oil burners,which is closer to our pellet stoves,as fuel is regulated,unlike a wood stove--

Cold combustion air is most often a concern when it is ducted to the burner from outside. Direct intake of outside air is common, for example, in mobile home furnaces. Although the combustion air is often pre-warmed in a “concentric-flue,” direct intake

sometimes is recommended in “tight” houses with insufficient air infiltration for combustion. Cold air is more dense, and contains more pounds of oxygen per cubic foot than warm air. (See Figure 3.) This means that, for a given air setting, the burner fan will deliver more oxygen when the air is cold than when it is warm.

Cold outside air typically increases chimney draft during the run cycle. If the burner is set up in warm weather, the cold winter combustion air (and increased draft) may cause the burner to operate too “lean”. This additional excess air may cause loss of flame retention or delayed ignition.

Have fun!!!

 

And I'm always losing air up my chimney since I have a pilot light going for my propane boiler (backups only work when they are primed to go as backups) - it may not be a huge amount, but I certainly don't want that exhaust being sucked back in because of the dryer , bath fan and perhaps both pellet stoves going at the same time! Oh, and the reason I have an OAK on my P43, even if this house still leaked like a sieve - it gets me the clearance to a window that I need for the exhaust.

I do not have OAKs on my stoves for efficiency, I have OAKs on my stoves because; CO2, the silent killer (and yes, I have several detectors in my house).

 

B I think you mean CO the silent killer. CO2 needs to get very very high to kill. CO not so high.

 

Your boiler uses a pilot light,and uses inside air?Very old.

 

Yes, it is >30 years old.

You are correct, my fingers got over ambitious with the typing