Fresh Air Intake Question

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Seeing as you've tried feeding it air I would think your right and the answer lies in the exhaust side.

You could try taping a mirror to a stick at a 45 degree angle and looking up through the clean out door or thimble, whichever is easiest. On many fireplaces the basement flue is cocked to allow for the firebox. You may not be able to see anything, maybe you will. A drop light fed down from the top is another old trick.
The old days foundation walls were just eight inches at least around here. Then the switch to ten inches made things worse. I was able to convince the contractors I worked for to revert the fireplace bump outs back to eight inches.

Are there any damper systems in the stove itself that could be not working correctly?


With the door open and burning for half an hour you should have a hellacious draft and things getting scary. If it's not roaring like crazy you indeed have a draft issue as long as there's plenty of air on the intake side.
 
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It could be that there is too much negative pressure in the basement for this to ever work well. I'm concerned that even if you got it to draw that the draft might reverse due to a range fan, furnace, or other exhausting appliance coming on. This could be fatal if not detected in time. Please be prudently cautious.
 
Seeing as you've tried feeding it air I would think your right and the answer lies in the exhaust side.

You could try taping a mirror to a stick at a 45 degree angle and looking up through the clean out door or thimble, whichever is easiest. On many fireplaces the basement flue is cocked to allow for the firebox. You may not be able to see anything, maybe you will. A drop light fed down from the top is another old trick.
The old days foundation walls were just eight inches at least around here. Then the switch to ten inches made things worse. I was able to convince the contractors I worked for to revert the fireplace bump outs back to eight inches.

Are there any damper systems in the stove itself that could be not working correctly?


With the door open and burning for half an hour you should have a hellacious draft and things getting scary. If it's not roaring like crazy you indeed have a draft issue as long as there's plenty of air on the intake side.
Seeing as you've tried feeding it air I would think your right and the answer lies in the exhaust side.

You could try taping a mirror to a stick at a 45 degree angle and looking up through the clean out door or thimble, whichever is easiest. On many fireplaces the basement flue is cocked to allow for the firebox. You may not be able to see anything, maybe you will. A drop light fed down from the top is another old trick.
The old days foundation walls were just eight inches at least around here. Then the switch to ten inches made things worse. I was able to convince the contractors I worked for to revert the fireplace bump outs back to eight inches.

Are there any damper systems in the stove itself that could be not working correctly?


With the door open and burning for half an hour you should have a hellacious draft and things getting scary. If it's not roaring like crazy you indeed have a draft issue as long as there's plenty of air on the intake side.

Seeing as you've tried feeding it air I would think your right and the answer lies in the exhaust side.

You could try taping a mirror to a stick at a 45 degree angle and looking up through the clean out door or thimble, whichever is easiest. On many fireplaces the basement flue is cocked to allow for the firebox. You may not be able to see anything, maybe you will. A drop light fed down from the top is another old trick.
The old days foundation walls were just eight inches at least around here. Then the switch to ten inches made things worse. I was able to convince the contractors I worked for to revert the fireplace bump outs back to eight inches.

Are there any damper systems in the stove itself that could be not working correctly?


With the door open and burning for half an hour you should have a hellacious draft and things getting scary. If it's not roaring like crazy you indeed have a draft issue as long as there's plenty of air on the intake side.
Hi Jo,
Thanks for the response. I was able to take a pic up the flue and was not able to see daylight. Had a guy from a local stove / hearth shop come out and he said he sees this quite a bit in masonry chimneys built by "old timer" Italian and French masons. He said you have to take off the shoulder stone and knock out the section of the clay flue where the offset is. He said the offset is so drastic that there is no way to get a liner through due to the liner making 3 points of contact. In addition, the ss liner was really ovalized and crimped where we tried to pull it through. This leads me to believe the mason may have cheated on the diameter of the clay liner at the offset. I just want to be sure that if I go and knock out the offset section of the clay flue, that it will work once we drop down the ss liner.
BTW - we have 10" foundation walls. If only we could go back and do it over again...
 
Hi Jo,
Thanks for the response. I was able to take a pic up the flue and was not able to see daylight. Had a guy from a local stove / hearth shop come out and he said he sees this quite a bit in masonry chimneys built by "old timer" Italian and French masons. He said you have to take off the shoulder stone and knock out the section of the clay flue where the offset is. He said the offset is so drastic that there is no way to get a liner through due to the liner making 3 points of contact. In addition, the ss liner was really ovalized and crimped where we tried to pull it through. This leads me to believe the mason may have cheated on the diameter of the clay liner at the offset. I just want to be sure that if I go and knock out the offset section of the clay flue, that it will work once we drop down the ss liner.
BTW - we have 10" foundation walls. If only we could go back and do it over again...


If your fireplace has two shoulders and two flues in the basement your stove guy may be correct. If it has only one of each I'd say he's nuts. :)
On a typical standard run of the mill fireplace with one flue in the basement the basement flue is situated towards the center of the house allowing that flue to run straight up except usually by the firebox where it must usually be bent out of the way, hopefully only slightly. The upstairs fireplace throat is then built off center towards that flue.
This leaves you one shoulder on the low side of the roof omitting wasted space. Granted it's not as pretty as everyone's vision of a two shouldered fireplace as being the norm but your probably figuring out why it's done that way.

It allows just one bend of a flue which is code. It brings the mass of the chimney towards the higher part of the roof so it's cheaper to build. Less brick above the roof.
Yes, I hate to say it but many if not most masons are quite capable of butchering a bend in a flue. There's very little wriggle room in an 8X12 for a 6" flexible. As masons we built them to work with old smoke dragons or furnaces not requiring liners.
Another big problem is that many architects and run of the mill plans are using empirical dimensions from days long gone. They've failed to incorporate new building codes and practices into the dimensions of foundation and framing given to the masons to work with. Basically trying to build 2015 fireplace in a 1950 shell. Quite a few masons wouldn't know the difference.

If you want to post or pm me some pics from outside I would have a much better idea of where your problem lies.

They do make oval liners but popular opinion of them here on this board seems negative. You'd also need a special brush to clean them. And there's no guarantee it will fit down either if someone seriously messed up the flue.
 
We end up having to open up chimneys a few times a year in cases like this. It is not that uncommon here either We just pull out a few brick or stone clear the offset and the liner usually goes through fine but then there are the ones where we have 4 or 5 holes in the chimney and we are 3 days into what we thought was a one day install. Liners are not always as easy as most on here make them sound
 
If your fireplace has two shoulders and two flues in the basement your stove guy may be correct. If it has only one of each I'd say he's nuts. :)
On a typical standard run of the mill fireplace with one flue in the basement the basement flue is situated towards the center of the house allowing that flue to run straight up except usually by the firebox where it must usually be bent out of the way, hopefully only slightly. The upstairs fireplace throat is then built off center towards that flue.
This leaves you one shoulder on the low side of the roof omitting wasted space. Granted it's not as pretty as everyone's vision of a two shouldered fireplace as being the norm but your probably figuring out why it's done that way.

It allows just one bend of a flue which is code. It brings the mass of the chimney towards the higher part of the roof so it's cheaper to build. Less brick above the roof.
Yes, I hate to say it but many if not most masons are quite capable of butchering a bend in a flue. There's very little wriggle room in an 8X12 for a 6" flexible. As masons we built them to work with old smoke dragons or furnaces not requiring liners.
Another big problem is that many architects and run of the mill plans are using empirical dimensions from days long gone. They've failed to incorporate new building codes and practices into the dimensions of foundation and framing given to the masons to work with. Basically trying to build 2015 fireplace in a 1950 shell. Quite a few masons wouldn't know the difference.

If you want to post or pm me some pics from outside I would have a much better idea of where your problem lies.

They do make oval liners but popular opinion of them here on this board seems negative. You'd also need a special brush to clean them. And there's no guarantee it will fit down either if someone seriously messed up the flue.
Great. Thanks for the response. I will take a pic of what we have and send along if I can figure out how to do it on this site. The chimney has 2 shoulders which gives it the tapered in look. If you are looking at the chimney from outside, the fireplace flue runs down on the left side and is a straight shot, (no bends). I know as I put the liner in with a couple friends. The basement flue is on the right and offsets to the right pretty hard at the shoulder then down to the basement thimble. We originally had a wood furnace installed when building the chimney, and the old frenchie mason was consulted while he was building the chimney.
BTW -I live in MA. not too far from CT..
 
Great. Thanks for the response. I will take a pic of what we have and send along if I can figure out how to do it on this site. The chimney has 2 shoulders which gives it the tapered in look. If you are looking at the chimney from outside, the fireplace flue runs down on the left side and is a straight shot, (no bends). I know as I put the liner in with a couple friends. The basement flue is on the right and offsets to the right pretty hard at the shoulder then down to the basement thimble. We originally had a wood furnace installed when building the chimney, and the old frenchie mason was consulted while he was building the chimney.
BTW -I live in MA. not too far from CT..
Hi Jo,
Here is a pic of what my chimney looks like. As I stated before, when looking at this pic, the upstairs fireplace flue is to the left and straight down. We currently have a wood burner insert in there. To the right of that is the basement flue which offsets to the right where the right side shoulder is. As stated in previous posts, I snapped a pic from below inside the flue and could not see any daylight up and out. I'm assuming it is a pretty nasty offset.
Any further help / input would be greatly appreciated.
 

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I use two 4" diameter pipes for fresh air intake.

I took out one of my basement windows, made a piece of plywood to stick in it, drilled 2 holes, and ran it through, down to the floor in the shape of a U. I can take pics if you wish. It works amazingly.
 
I use two 4" diameter pipes for fresh air intake.

I took out one of my basement windows, made a piece of plywood to stick in it, drilled 2 holes, and ran it through, down to the floor in the shape of a U. I can take pics if you wish. It works amazingly.
Yes, If you could send pics that would be great. Thanks -
 
Will do when I get home from work. Total cost was around $44. Easy to remove too. My friend has the exact same setup required for his Yukon Eagle.
 
I apologize for the delay on taking pictures. My wife is being induced for our first baby tomorrow, and I've had a number of false alarms lately.

Here's the documentation from Yukon Eagle, and here's what I did. I couldn't get 8" piping, so I did 2 4" piping. It works well.












Total cost $44.
 
I added a screen to the outdoor caps, shoved inside them so critters couldn't find their way in. Come summer, i'll put a block of wood over the holes so bugs don't make their way in.

a few things you'll notice.

1.) Your basement will get noticably cooler. Maybe 5 degrees or so.
2.) You'll FEEL the fresh air coming in when you walk by. It feels like a hair dryer coming out of these holes. It's pretty wild.
3.) You'll have less back smoking. I still have some, but not nearly as bad. Also, my wood consumption plummeted, and my burns were much cleaner.
 
Hi Jo,
Here is a pic of what my chimney looks like. As I stated before, when looking at this pic, the upstairs fireplace flue is to the left and straight down. We currently have a wood burner insert in there. To the right of that is the basement flue which offsets to the right where the right side shoulder is. As stated in previous posts, I snapped a pic from below inside the flue and could not see any daylight up and out. I'm assuming it is a pretty nasty offset.
Any further help / input would be greatly appreciated.

Sorry for the delay.
Not much help I'm afraid. Everything looks good. A 68" base is perfect IMO for a standard fireplace. The shoulders are set high enough that a crazy flue angle is not needed. Though any angle in a flue can be real trouble when trying to get a liner down.
I still worry about the 10" foundations on the bump out. Pushes your flue 2" closer on both the side and back. The few I did I chopped away at the top of the foundation to help lessen the effect. Raised hearth is easier than flush also.
Personally I would think hard about using an oval liner if the proper brush can be obtained. I'm not a big fan of smashing through chimneys and flue tiles to insert liners. I would worry the patch job would leave openings between the liner and cavity of the chimney creating cool spots. You also might find you need to break through the base right near the bottom also.

Th photos j7art2 posted are the intake diagrams I referenced early in this thread but could not remember where I saw them.
I do not see an air intake on your chimney in the photo. Perhaps it's lower. The single air intake usually used in a fireplace is probably not large enough for a direct feed to a woodstove though it could help in a passive setting. I have two in mine because of the firebox size.
 
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I am having trouble keeping our newly, (basement installed), Englander NC30 stove running with the door closed. Even with the draft rod fully opened, it tends to go out when the door is closed. Our house was built in 09' and is very tight. We had an energy audit conducted last year, and were told it was almost too tight. After researching here and on both Englanders and Woodstocks websites, I decided to try the outside air intake kit. This was also suggested by the folks at Englanders tech dept.- My Question is..., I have an outside vent on our masonry chimney that used to be used for the combustible air for the fireplace upstairs. We installed a Hampton HI 300 insert in the fireplace 3 years ago, (love it), making the outside vent useless. Could I tie the fresh air intake to the clean out door for the upstairs fireplace chase seeing as how there is a vent above that allows for outside air? The reason I would like to do this is b/c our propane furnace is direct vented out on the wall aside the stove pipe and I would have to have a very long run of 3" tubing to get to the opposite wall and out..
Any thoughts?
Have you tried checking the draft with a gauge? Maybe this can rule out the flue before doing extensive damage to the chimney.
 
What is the best way to measure the draft? I really would like to exhaust all possible avenues before getting into ripping apart my chimney that was built in 09' and was very expensive! Could there possibly be something wrong with the Englander Stoves draft control? Has anyone ever heard of things similar to this happening on the Englander stoves? As I said previously, we had a wood burning furnace in their previously, and we never could get it to work properly. That, along with the fact we couldn't get the liner down (and it ovalized to a small diameter), is what leads me to believe its the flue. I really hope not.
 
So, I actually dropped a 6" ss liner in the chimney this past summer. We had to take the shoulder off and knock out a couple bricks to get it to go down, but it is in. Unfortunately, when we fired up the stove for the first time with the liner in, I got the same result. When I shut the door, the fire went out! I couldn't believe it! Now I've spent almost $600 on dropping a liner down and got the same result? WTH do I do next? I've spoken with Englander after waiting on hold for an hour or more, and they said it was my connection on the top of the stove which is BS. The guy that helped me install the liner and stove pipe works for a very reputable stove shop in our area and does installs all the time. It is a 45 double wall connected to a double wall 48" pipe to a 45 that goes to the thimble in the masonry wall.
What do I do next? Someone please help! Someone in this previous (saga) post mentioned it could be a severe negative pressure issue In the basement? How do I check that?
 
Open a close by window an inch and see if that improves behavior. If so the stove may need an outside air supply
 
This spring I moved to Vermont and dragged my kicking and screaming PH with me, not until I told it that it could have an outside air intake would it calm down. So I began planning a path and quickly realized that it snows in Vermont and the original air entrance would quickly be covered by snow. So, up above the firebox it went. Having zero problems, EZ start. Unfortunately, after months of looking at a cold lifeless stove, I end up working of all places in Saudi Arabia right when heating season starts. My girlfriend sends me pictures and I feel the heat. Unbearable heat.
 
Open a close by window an inch and see if that improves behavior. If so the stove may need an outside air supply

Semipro and begreen,
I have already tried opening the window closest to the stove in the basement. I even have gone as far as leaving the walk out basement door wide open that is 6 feet from the stove to no avail. The fire just goes right out with the door closed. Last year I spoke with the folks at Englander, and they convinced me that it was a lack of air and I purchased the outside air intake kit, (OAK), from Englander. I hooked it up and got the same results. Super frustrating. Not sure what I can do next. Could it possibly be a whole house pressure issue?
 
Still fighting this?

Bottom line forget pressure issues. You've offered it the correct venting and air intake. It burns fine with the door open but goes out when it's closed. In my uneducated opinion there's only one possibility. It's the stove.
Possibly a disconnected air damper? I'm not familiar with that stove, not sure how it works. I would be looking over the guts of that stove and determining how it's supposed to,work and why it doesn't.
See if the manufacturer can be more helpful NOW that you've exhausted all the possibilities they expressed.

Last drastic Hail Mary test. Get the cheapest if not free old fashioned smoke dragon you can find on Craigslist. Drag it into the basement and connect up the exhaust. If it works you know the weak link.
 
Still fighting this?

Bottom line forget pressure issues. You've offered it the correct venting and air intake. It burns fine with the door open but goes out when it's closed. In my uneducated opinion there's only one possibility. It's the stove.
Possibly a disconnected air damper? I'm not familiar with that stove, not sure how it works. I would be looking over the guts of that stove and determining how it's supposed to,work and why it doesn't.
See if the manufacturer can be more helpful NOW that you've exhausted all the possibilities they expressed.

Last drastic Hail Mary test. Get the cheapest if not free old fashioned smoke dragon you can find on Craigslist. Drag it into the basement and connect up the exhaust. If it works you know the weak link.

Yup. That's exactly what I think the issue is as well. I'm thinking it has something to do with the draft rod. Doesn't seem to appear to get more air when opening it up. I just hope Englander will stand behind their product and help me out. I've pretty much exhausted every avenue at this point. I just need one of their local reps to swing by and give it a look see.
 
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I suggest you start a new post. This post is titled and focused on intake air issues. Since you're pretty much determined that's not the problem I'd suggest you approach your problem differently.

This is an older post and I don't recall the content but the first issue to address with burning issues like you're describing is fuel quality.
 
Semipro, I appreciate your question, however, I have been burning wood for a while now and only burn seasoned hardwood. We have a Hampton HI300 in the upstairs hearth that we use pretty consistently with the wood I'm using in the NC30 downstairs. I know the difference between seasoned and unseasoned wood. Been burning upstairs for about 2 weeks now with excellent results...
 
I was just using wood quality as an example. You seemed to have narrowed things down to a problem with your stove rather than "fresh air intake". I'm just saying a post with a title that contains the stove model and a more general description of your problem might attract more knowledgeable readers. who can offer help.
Enough said.
 
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