Bringing "outside air" from the basement via the ash pit, brilliant or dumb?

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sksmass

Member
Dec 21, 2009
203
Western MA
I am pondering the wisdom of installing an outside air kit on my fireview. It is a fireplace install and I would feed the OAK into the ash pit. I could then leave the ash pit clean-out door ajar in the basement so the combustion air would be drawn from the basement rather than the living room I am trying to heat.

My logic is that I would rather create cold drafts in the (already cold and drafty) basement than in my heated living space. The house is not that tight, an OAK is certainly not necessary for the stove to pull adequate combustion air. The only advantage of an OAK in my situation would be in trying to influence the part of the house from which the air would be taken. That is, to try to keep the cold drafts away from the warm people.

The ash pit is really cavernous. It serves three masonary fireplaces.
 
Pulling more cold air into the basement during the cold of winter is a bad idea. It sounds like an invitation for freezing pipes. When one is heating 24/7 with wood, this is a very real concern. If the basement is leaky, seal up those leaks well and duct to OAK to outdoors.
 
Is this an outside wall chimney? Can you drill through your chimney from the outside into your ash dump and vent your oak that way? IMHO even a leaky house can benefit from an oak.
 
Todd said:
Is this an outside wall chimney? Can you drill through your chimney from the outside into your ash dump and vent your oak that way? IMHO even a leaky house can benefit from an oak.

No, the chimney is smack in the middle of a brick colonial house. To really get an OAK all the way to the outside air would require so much ducting and drilling that I'd never undertake it.
 
i am in a similar situation... i am thinking moving my insert out putting oak on running some type of pipe down the ash all the way over to a window which will have to be fitted for a pipe.. problem is for such a long run i might need a fan on it as well as run a 6 inch pipe since we are going down 10 ft then up 7 ft and across 15 ft... might just be better to crack a window..... and fyi .... i have left my ash door open and it doesnt really draw air from there .. you cant feel air getting sucked in .. it will draw from where ever is easiest

hey your from western mass!!!! what part???
 
iceman said:
...for such a long run i might need a fan on it as well as run a 6 inch pipe since we are going down 10 ft then up 7 ft and across 15 ft... might just be better to crack a window.....

Sounds similar. A long length of ducting and lots of bends and elbows would be required to get to daylight. I worry that any OAK that needed to go to such great lengths would actually decrease the efficiency of the stove because of the friction losses of trying to pull combustion air through all that resistance. What we might end up with is a stove that burns cold outside air but does so really inefficiently.
 
sksmass said:
iceman said:
...for such a long run i might need a fan on it as well as run a 6 inch pipe since we are going down 10 ft then up 7 ft and across 15 ft... might just be better to crack a window.....

Sounds similar. A long length of ducting and lots of bends and elbows would be required to get to daylight. I worry that any OAK that needed to go to such great lengths would actually decrease the efficiency of the stove because of the friction losses of trying to pull combustion air through all that resistance. What we might end up with is a stove that burns cold outside air but does so really inefficiently.


yeah, looks like thats where we are headed... i wish i would have found this site about 8 yrs ago then i would know better
 
But you very well might find after the install that you do not need the OAK. We planned on putting one in but have not as we simply do not need it.
 
After getting all this good input and considering it for awhile I've decided against trying to do anything fancy with an OAK. The benefits don't seem greater than the likely cost. I'll just install the Fireview and see what happens. If I notice any increase in cold drafts in the living area then I'll just tell myself I'm helping to clear the house of radon. %-P
 
sksmass said:
After getting all this good input and considering it for awhile I've decided against trying to do anything fancy with an OAK. The benefits don't seem greater than the likely cost. I'll just install the Fireview and see what happens. If I notice any increase in cold drafts in the living area then I'll just tell myself I'm helping to clear the house of radon. %-P
Yep dont fix it till its broke, see how it works and go from there.
 
here’s a little trick i learned from a rep we have in canada.

if you cannot directly connect an OAK but need makeup air and do not want just an unregulated open hole , make a simple airlock with some PVC and a 5 gallon bucket.

go through the basement wall (aboveground) and insert your PVC (3 inch would be preferrable but 2.5 will still work) after coming in through the wall elbow down and carry the pipe to about 3 inches off the floor INSIDE the 5 gallon bucket.

here’s how it works, the negative pressure in the house will pull the air in and being as the air will be colder than the air in the basement the bucket will “trap” it and only allow enough out to satisfy the pressure difference in teh summer it will not trap as much air as the temp differential is not present but in winter when you do not want a big air “leak” the colder it is outside the lesser amount of air is pulled out unless you are running the stoves/fireplaces which increases the draft and pulls more make up air out. it really works.


oops re-read didnt catch the stove was not gonna be in basement
 
Brilliant!

I have a similar situation in my house. An OAK would have required a long, twisty run, I didn't want to drill through 18" of masonry to run an OAK, and the ash pit opening was just so perfectly conveniently underneath the stove. Putting the air intake into there works great. The basement isn't too cold - it's two to four degrees cooler but still above 40 degrees. And when it is really cold outside, I'm also running the boiler anyway, which keeps the basement a little warmer.

In fact, the basement is better as a root cellar than before.
 
same setup but my OAK continues out the ash door in the basement to the outside thru a boarded up window. I think you are on the right track.. just find a way out of the basement now!
 
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