Fireplace air intake?

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Bluelighttaxi

New Member
Oct 15, 2020
5
Maine
Hello All,

I have recently pulled a propane fireplace insert that was installed in my house prior to purchase. We have a beautiful natural stone open fireplace that is the center point of our open concept living area. My wife and I want to go back to the occasional real wood fire in the fireplace. Clay liner and chimney is in excellent condition. House and chimney built in 1990.

I’ve located what looks like possibly an air supply built into the lower right side of the fireplace. Looks to be about a 2” steel pipe with a sliding steel gate type damper/door combination. A flashlight inside shows that it takes a 90 degree bend toward the back of the fireplace, not sure where it goes from there as I’ve never observed any sort of air supply piping outside of the fireplace or the chimney. I have attached a photo, any help in confirming what this is would be greatly appreciated!
Paul

6CA08C73-B3FF-4F9F-B164-7D902F190E69.jpeg
 

webby3650

Master of Fire
Sep 2, 2008
11,061
Indiana
Unless it was vent free, you might have been better off with the gas insert. Push button start, no mess goes a long way.
 

Rob711

Feeling the Heat
Oct 19, 2017
431
Long Island, ny
I have no idea, I’d believe someone if they told me it was to help supply outside air. That would drive me insane though. Where does it go!!!? Can you fish a camera in there? Maybe it’s a air supply for a secret bunker!
 

clancey

Minister of Fire
Feb 26, 2021
1,398
Colorado
Now that's intriguing and maybe there is a pot of gold or a buried treasure...Get that camera "ready".. Could it be maybe a damper or something like that--interesting...hope someone knows..clancey
 

webby3650

Master of Fire
Sep 2, 2008
11,061
Indiana
It supply's make up air. It will be almost useless though. A 2” pipe won’t supply enough air for a 12” flue, the additional air will be pulled from the living space. It might terminate in the crawlspace. It could be a Highway for rodents if the end doesn’t have a screen on it.
 

clancey

Minister of Fire
Feb 26, 2021
1,398
Colorado
Now this is a stupid question but could some kind of emergency water pipe be hooked up to that--just trying to figure this out...Wow a highway for rodents--how terrible...but I can see it...clancey
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,515
central pa
Now this is a stupid question but could some kind of emergency water pipe be hooked up to that--just trying to figure this out...Wow a highway for rodents--how terrible...but I can see it...clancey
Why would you want a water pipe?
 

clancey

Minister of Fire
Feb 26, 2021
1,398
Colorado
Maybe some kind of a safety back up like a sprinkler system or something---I know its crazy but just trying to figure out what that pipe and vent was for---lol ....I said it was stupid but trying to figure out "why" just so different especially since the pipe would not give no adequate air supply----so you think that it would bring heat to the attic if it goes there???clancey
 
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Reactions: bholler

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,515
central pa
Maybe some kind of a safety back up like a sprinkler system or something---I know its crazy but just trying to figure out what that pipe and vent was for---lol ....I said it was stupid but trying to figure out "why" just so different especially since the pipe would not give no adequate air supply----so you think that it would bring heat to the attic if it goes there???clancey
Putting water in a woodstove or fireplace is not a good idea and can have very dangerous reactions
 

clancey

Minister of Fire
Feb 26, 2021
1,398
Colorado
Well that's nice to know---thanks...can you tell me how that would work? What reactions like steam or something like a cooking pot that you put water into to cool it off...Does it splatter or something? Good to know bholler --thanks so I guess my idea is out--lol well thinking further on this situation with that piping and could it be some kind of old gas pipe line or something...? It was built in 1990 maybe the owner will come back and give us a update especially with a camera in there....so curious...maybe a pot of gold....lol lol Thanks bholler...clancey
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,515
central pa
Well that's nice to know---thanks...can you tell me how that would work? What reactions like steam or something like a cooking pot that you put water into to cool it off...Does it splatter or something? Good to know bholler --thanks so I guess my idea is out--lol well thinking further on this situation with that piping and could it be some kind of old gas pipe line or something...? It was built in 1990 maybe the owner will come back and give us a update especially with a camera in there....so curious...maybe a pot of gold....lol lol Thanks bholler...clancey
When you put water on a fire or very hot object it very quickly converts to steam. When it does that it expands 1600 times. When that happens it can cause lots of damage very rapidly. We have seen chimneys blown apart by someone dumping water down a burning chimney
 

webby3650

Master of Fire
Sep 2, 2008
11,061
Indiana
There’s no reason to look into it any further. It’s to supply make up air for the fire. You just need to find out where it terminates. If there no grill on the outside, look in the crawlspace under the house if you’ve got one.