NC30 - Outside air kit(OAK) thoughts?

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Longsnowsm

Member
Oct 11, 2014
24
Missouri Ozarks
I have a question for all of you NC30 owners. What are your thoughts about the outside air kits(OAK) for the NC30? Do you have the OAK? Do you like it, does it help? Would you recommend installing the NC30 with the OAK? I found the kit on the Englander site for $72. What are your thoughts? Thanks.
 
Only one of the three sources of firebox air is fed by the nc30 oak system. Pretty pointless.
 
I have a 30-NC, but did not hook up the OAK. My flue/chimney is roughly 20ft. combined, so I get plenty of draft and have had no reason to hook it up.
 
Pretty sure it all depends on how air tight your house is. I don't have one on mine. I can feel it pulling air from my basement while burning.
 
When I had my 30-NC installed an OAK was one my non-negotiables (after safety). No way did I want the equivalent of 3" hole in my house sucking in cold air.
 
I believe in OAK systems that actually use outside air for combustion. My last two house stoves used their OAK connection for 100% of air that went into the stove and up the flue. Sealed combustion you might say.

Some stoves don't do this. The NC30 only uses that OAK connection to feed the primary air which is generally shut down most of the way during the burn. The NC30 doghouse air supply that is always full throttle sucks from two holes under the stove and NOT the OAK connection. The secondary air system that feeds the tubes on the firebox roof are fed full throttle all the time from a rather large hole near the back of the stove and NOT the OAK connection.

Due to the above OAK deficiencies, the connection of the OAK tube on the NC30 is not really important. I would do it anyway since the my permits have always required it and since I already have the OAK plumbing in place.
 
Contrary to the opinions above, the dog house is affected by the control up front, on mine anyway as when I close the control the dog house also reduces its velocity. Front holes by legs , I was under the impression that they were air feed for the glass wash. Secondairy air feed small sq. hole in back- yes. I have oak set up on mine- believe me when I say I can hear the air being pulled in on that connection when the stove is rolling. As I do not particularly care for a small hurricane of cold air along the floor feeding the stove without it. And the primary question is why would you not connect the oak, if possible, rather than creating a large negative pressure situation which would further reduce the ability to keep your home warm? Note this is not my first secondary combustion stove, just larger than the previous one of a different make. My Nc is about 5 years old. 98% of my heat is supplied by the 30 (2000 sq ft split ranch). The T-stat is set at apx 65F for the NG unit as a back up as there are times when my work hours get horrendously long ( up to 18 hours in winter). even with that my winter utility bills are generally less than $100/mo. of which 50% or more is all the add on charges. If I pay $7.00 for NG it will cost me $16 in add on charges and they keep raising those charges every year.
I did ask Englander sometime back if I could hook the secondary intake to the oak also- I didn't get a nay answer but also did not get a positive yes. It would of course require a bit of fabrication for a oak plenum to feed both intakes from a single line and may require a larger dia. oak feed line.
Going back many years in the yea or nay conversations on oaks- there are suggested practices for make up air without unduly cooling the dwelling as pure infiltration would, also for pre-warming ( using ambient room temps) the make up air. Much of this has been lost in the constant Ford ,Chevy,Dodge, bickering concerning oaks. Then of course you have the arm chair engineers who have never burned a match adding their 1/2 cents worth in and muddying the waters further. I grew up with wood , coal ,oil, gas of one type or another (progressively), in open fireplaces or appliances in dwellings that were basically a sieve to sealed as tight as a hermetical sealed plastic bag ( you really do not want that as it leads to all kinds of other difficulties). sorry got a bit long winded
 
Contrary to the opinions above, the dog house is affected by the control up front, on mine anyway as when I close the control the dog house also reduces its velocity.

False. The primary air control only regulates the feed to the airwash. The holes under the stove in front provide unregulated feed to the doghouse vent. Paging @BrotherBart to the front.
 
All primary air in the 30 comes in through the intake in the back. Then through channels under the firebox to the manifolds on each side of the door then down over the glass and is deflected back into the fire by the deflector plate in the front of the stove. That is the only regulated intake air. The secondary and doghouse air are unregulated.
 
Were it not for having to punch a hole in the back of my fireplace I would have an OAK on my 30. Dragging as much intake air from the great outdoors without it having to be sucked through leaks in my house would be a good thing.
 
Riddle me this - when the control is full pushed in towards the unit why does the dog house volume die off if it is not controlled in some fashion? we have no damper on the exhaust none on the secondary and you are saying none on the dog & airwash. yet closing the primary on my unit does reduce the velocity of the dog house? Note only the last 1/2" of travel has this effect( could be more but not particularly observable until this point) weather full blast burn or just a small warm up, secondaries raging or none at all. Therefore based on this observation something somewhere is redirecting or closing/restricting that feed. In any burn restricting the primary should then increase any of the none controlled feeds due to the draw of the flue with in the limitation of the size of the particular intake in question.
I wish that all companies would give a clear diagram of air feeds so we would positively know what we are dealing with and which are controlled or not. I know it works as it is, just do not like being in the dark. And no I do not wish to cut the unit apart to find out, leastwise not until it is no longer useful. Course with Englander I could be long gone before it gets to that point.
Not arguing, just trying to understand why my observations seen to be out of wack.
 
The doghouse air is unregulated so the flow through the fixed orifice can only vary with varied draft. You aren't measuring that flow, just observing flames in a pile of wood to make assumptions. The airwash air is regulated, it is the only regulated source of combustion air. The airwash air is a much bigger source than the doghouse hole and when you shut off the airwash air you can usually snuff all flames on the wood which means your only way of measuring doghouse flow is lost.

Also draft is powered by heat. When you cool the fire, you reduce the draft which reduces the flow from the doghouse.
 
When it comes to combustion, cold dense air is a good thing. I'm figuring out how to get it plumbed into my basement currently. I also don't like the fact that when firing up the stove and the furnace is still active that air is being consumed by that also.

Good info! Been wondering how the air works in it!
 
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