Enviro Mini - Sorry - But Yet Another OAK (Outside Air Kit) Question

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Any QuadraFire owners out there with an OAK. My dealer seemed sorta cynical about it mentioning something about pests getting access but I have a HUGE problem with cold air getting sucked up from the basement. When that stove runs that floor gets cold! Part of that is obviosuly due a furnace no longer heating a basement but I can feel the air whirring up from downstairs. Efforts to ask the wife to close the basement door have failed so I have to family-proof this thing.

I have an OAK on mine. I did a pretty good job sealing all holes, and cracks in my system.

Even if you don't, the air will take the path of least resistance. It would rather come in that 3" vent that's a few inches away from the intake source, than come in through your bedroom window 35' away. IMO.

OAK's always help....
 
Many say that installing an OAK really has more to do with overall efficiency of the heater. I have to disagree. Heating a small home with such an appliance as a pellet heater can be harmful to the health of the occupants if the air is not handled properly.

The mini is not alone in the line up of Enviro pellet stoves that are NOT readily equipped to handle an OAK properly. In fact, many manufacturers neglect to tie in the heater cartridge (igniter) with the combustion air port. For a heater to be maximumly efficient and truly separated from the inside air, ALL combustion air which enters the appliance should be completely separated from the convection air or room air.

Last winter I ordered a new Magnehelic Gauge to read 0-0.25 inches of water column. I was setting it up in my kitchen and was immediately thinking it was broken, as it measured .09 while just sitting the table. I shut down the pellet stove across the living room and was astounded that the gauge went back to zero. Immediately.

This prompted me to install an OAK. Let me tell you, it was not easy to completely seal the stove up, even with the recommended pipes.

I did talk with my pediatrician though about the effects of my kids living in a house that was under constant negative pressure. She called it a "sick house" or a house that does not produce make up air.

This is caused by too much air leaving the house through various sources (a pellet stove) and the inability of replacement air to have an easy access into the house replacing the air and oxygen used when the living conditions such as heat is rising, exhaust fans are operating, or combustion appliances and people are using up the air and oxygen.

This is why all mobile homes require an OAK. I would lump in any home under 1500 sqft too, which mine is.

Most OAKs take cold and sometimes damp air from the outside which unfortunately reduce the overall efficiency of the pellet heater. It's like putting damp and cold wood into a wood stove!

The absolute best solution is to pre-heat that outside air to make it warm and keep it dry with Selkirk DT venting that I install.

see pic below
 

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As another Long Island Mini owner thinking about adding an OAK, I would be interested to know what you finally did about outside air.

I replaced my vent/thimble this year because I had the house re-sided. I installed a Simpson Duravent thimble with a build in OAK. Even though it doesn't terminate at the burn pot, at least I know the stove isn't competing for air.
 
I went ahead and had an OAK installed. Even though it is not a perfect connection as detailed above, it has allowed me to leave the forced air vents from the gas furnace open that were the stoves source for air, dragging the cold basement air up into the house. Everyone of them, we live in a small cottage, was a torrent of air.
 
Most OAKs take cold and sometimes damp air from the outside which unfortunately reduce the overall efficiency of the pellet heater. It's like putting damp and cold wood into a wood stove!

The absolute best solution is to pre-heat that outside air to make it warm and keep it dry with Selkirk DT venting that I install.

see pic below


Are you saying that preheating the air drys it? Where does the moisture go?
 
OK Smart Enviro owner (Proud owner of 3 enviro stoves. On the mini and most enviros, the fresh air tube inlet is just a guide spot. Take a 1 inch or 1.5 inch metal tube and connect it from the stoveback tube and connect it mechanically (via screws and L bracket to the inner stove shell. Put hi temp silicone in air tube inside to block out all internal house airflow into the stove. Then hook up flex tubing through the wall to outside of house. Remember to seal all external connections with silicone and appropriate screens to keep critters out. Outside air will almost always make a stove run better, cold dense combustion air is great if you seal the intake path to the stove only and do not put another hole in your house to let cold air in. As an installer, I see it a lot. Don't forget to properly adjust the air damper too. In case anyone is wondering, lots of manufacturers leave outside air inputs open, Breckwell inserts are known for it, kinda hard to hook up to stove body too. They make nice stoves too. Hope this helps.

Stovelark
Enviro 1700 FS wood
Enviro EF3 FS
Enviro Empress Insert (can you tell I like ENVIRO?)

Thanks, this answer some of my questions about the OAK connection on the Mini I'm installing right now. I also though it was missing parts to the burn box. Now, what about the large air intake hole between the draft slider and the combustion fan. That is strange design to me as well. I guess the design mixes house air with exhaust air on right before the combustion fan. I guess the design is like the air max flapper on my furnace exhaust ducting.
 
Also it looks like my stove arrived with the "with the little flapping door" missing!!! Will have call dealer on Monday. Is the door optional. Thinking about making a temporary solution. The door is to the fan box where that vacuum sensor hose terminates.
 
Here! Here!
Before you jump on the"fake OAK" bandwagon,Realize a lot of european stoves were/are made this way,some american stoves have bleed holes(shudder everytime someone writes they taped/blocked them).Cold air reduces availible heat,hence the design of your stoves pipe system,same as a bixby.There also may be safety reasons for these designs,as something bad could happen with total air blockage.
 
OK Smart Enviro owner (Proud owner of 3 enviro stoves. On the mini and most enviros, the fresh air tube inlet is just a guide spot. Take a 1 inch or 1.5 inch metal tube and connect it from the stoveback tube and connect it mechanically (via screws and L bracket to the inner stove shell. Put hi temp silicone in air tube inside to block out all internal house airflow into the stove. Then hook up flex tubing through the wall to outside of house. Remember to seal all external connections with silicone and appropriate screens to keep critters out. Outside air will almost always make a stove run better, cold dense combustion air is great if you seal the intake path to the stove only and do not put another hole in your house to let cold air in. As an installer, I see it a lot. Don't forget to properly adjust the air damper too. In case anyone is wondering, lots of manufacturers leave outside air inputs open, Breckwell inserts are known for it, kinda hard to hook up to stove body too. They make nice stoves too. Hope this helps.

Stovelark
Enviro 1700 FS wood
Enviro EF3 FS
Enviro Empress Insert (can you tell I like ENVIRO?)


I would be afraid of voiding any warranties by doing this. The enviro, like many other stoves, do not direct the outside air into the air intake port. Why they want to mix inside air is anyone's guess. Could be safety reasons... ie the oak gets blocked or it also could be they want to blend the cold air with warmer air before combustion. "Gerryrigging" your own thoughts on what an OAK should be could be dangerous. This is one of the reasons why I do not feel the urge to install the OAK. Until I figure a way to install some sort of automatic damper to open and close the air supply, I will not be using one. My stove does not run 24/7, so why would I want cold air pouring into my room. I have enough leaking window that already does this.. I do not need any more drafts.
 
I would be afraid of voiding any warranties by doing this. The enviro, like many other stoves, do not direct the outside air into the air intake port. Why they want to mix inside air is anyone's guess. Could be safety reasons... ie the oak gets blocked or it also could be they want to blend the cold air with warmer air before combustion. "Gerryrigging" your own thoughts on what an OAK should be could be dangerous. This is one of the reasons why I do not feel the urge to install the OAK. Until I figure a way to install some sort of automatic damper to open and close the air supply, I will not be using one. My stove does not run 24/7, so why would I want cold air pouring into my room. I have enough leaking window that already does this.. I do not need any more drafts.
Good to see some common sense.Appears some people did not pay attention in school.One reason for a blended system is in case of house depressurization,smoke does not get drawn into house as bad.Do not have an oak as I shut stove off during day a lot,and run it on low a lot,however adding a water valve to a oak would be easy.European stove installers sell oak sets with a simple shutoff made in pipe,if you are interested. http://www.woodheat.org/the-outdoor-air-myth-exposed.html
 
The design does not make sense. My US Stove OAK is a direct connect to the outside so there is no cold air dumping into the room.
 
Good to see some common sense.Appears some people did not pay attention in school.One reason for a blended system is in case of house depressurization,smoke does not get drawn into house as bad.Do not have an oak as I shut stove off during day a lot,and run it on low a lot,however adding a water valve to a oak would be easy.European stove installers sell oak sets with a simple shutoff made in pipe,if you are interested. http://www.woodheat.org/the-outdoor-air-myth-exposed.html

Pellet stove is a forced air system - so does this apply? Anyway - a value would be must and you have to now remember to turn it on and off.
 
Pellet stove is a forced air system - so does this apply? Anyway - a value would be must and you have to now remember to turn it on and off.
What part not apply?Also,most of the rest of the world does not waste heat the way we do,so walking over and shutting a valve is nothing to them.(heat costs lots more for them)
 
My stove is missing the backdraft flapper part 50-1542. Dang it. I will make one till I can get the OEM part.

On my Maxx, I found I was getting very little draft through the OA pipe. I removed the backdraft flapper and it improved enough to at least hold a piece of paper over the open end of the pipe - but not even dimple it. I'm starting to think about a vacuum controlled flapper valve in the OAK.

I think too much.

Cheers,
- Jeff
 
On my Maxx, I found I was getting very little draft through the OA pipe. I removed the backdraft flapper and it improved enough to at least hold a piece of paper over the open end of the pipe - but not even dimple it. I'm starting to think about a vacuum controlled flapper valve in the OAK.

I think too much.

Cheers,
- Jeff
Actually good idea.
 
There is only one reason why all stoves do not come with a sealed system, heat exchanging OAK. Cost.
Manufacturers can give you all kinds of crazy reasons but it all comes down to the fact that it is more expensive to design and build. They are just saving money, the rest is nonsense.
We can agree to disagree.But why do some stoves that oak is directed to firebox have holes drilled and a stopper flange so they cannot be covered?I think engineers know more than us.
 
Thanks for reply.I see you,me and don agree preheated air is better for combustion,especially in colder weather.As my unit is old,that would make sense,and I have heard enviros had wind problems,so that was their fix.You do know you are going to make some people mad with that "running in cold climate" statement!!!! By the way,montana is generally way warmer than the upper mid west(michigan,etc) just cooler weather lasts longer out here.Lots of days stove only runs a few hours.
 
What I meant was there are a lot of oak people that think it makes all stoves run better,all weather,all oak configurations.But in the last 2 weeks it has been anywhere from -30 to 50,but I am in the mountains,6500',most people live in the valleys.
 
Do some research,i run an austroflamm,has a mass air flow sensor(bmw)was specifically designed to run at all altutides.Some of the Italian stoves use this system now,so suppose they would work.Have worked on other stoves at higher altitudes,usually have to bypass vacuum sensor(older ones) but if had pressure sensor was ok(some whitfields.etc)Best to have short exhaust when going higher in mountains.This is just my experiences,auto mechanic by trade.Best way to approach problem(altutide)is speed up combustion blower.Need more volume for same o2 content.
 
I agree.The older st croix multi fuel manual control stoves do well up high,do not know about corn.If you have rich customers,take a look at rikas pellet and wood combo stove.
 
On my Maxx, I found I was getting very little draft through the OA pipe. I removed the backdraft flapper and it improved enough to at least hold a piece of paper over the open end of the pipe - but not even dimple it. I'm starting to think about a vacuum controlled flapper valve in the OAK.

I think too much.

Cheers,
- Jeff

Why remove the backdraft flapper? If it removed, then the combustion fan will draw all the air through the backdraft hole instead of through the burn chamber.
 
Why remove the backdraft flapper? If it removed, then the combustion fan will draw all the air through the backdraft hole instead of through the burn chamber.

Well I don't know where that piece is on the subject stove, but on mine it is in the OAK inlet. I found that running on pretty high setting I was not drawing enough air through the pipe I've attached to matter. I pulled the pipe off and could see the flap moving ever so slightly - not much draft happening there. So I made sure it wasn't bound up, then pulled it. Now my OAK pipe can at least hold a piece of paper in place - before not even that.

Cheers,
- Jeff
 
Well I don't know where that piece is on the subject stove, but on mine it is in the OAK inlet. I found that running on pretty high setting I was not drawing enough air through the pipe I've attached to matter. I pulled the pipe off and could see the flap moving ever so slightly - not much draft happening there. So I made sure it wasn't bound up, then pulled it. Now my OAK pipe can at least hold a piece of paper in place - before not even that.

Cheers,
- Jeff

Ahhh, OK, so your OAK has a damper. Ya, you got have that probably wide open for sure.
 
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