Condensation Leakage from Stovepipe
LESLIE: William in Tennessee, you’ve got The Money Pit. How can we help you today?
WILLIAM: Well, I’ve got a wood stove in my living room. And I have my stovepipe coming out the back, through an elbow, going straight up about 5 or 6 feet and then got another 90-degree elbow. And it’s going through the wall, through an insulated piece of stovepipe, to the outside and then another 90-degree bend and going up about 4 or 5 feet to my – to the cap (inaudible at 0:09:59).
TOM: You have three 90-degree bends in the wood-stove pipe?
WILLIAM: One, two – yeah, got three in it. And what’s happening is right behind my wood stove, I have a big, 3×6-foot plate-glass window that’s framed in. And we’re getting some leakage of black creosote liquid. It’s condensation or water of some type. It’s got creosote in it. It is actually dripping down and running down the inside of the frame of the window.
So the leak is in the – is inside the wall somewhere. And I have sealed and done everything that I possibly can and I don’t know how to stop this leak or what could be causing it or where to go from this point.
TOM: So, does the pipe exit the wall above the window?
WILLIAM: Yes, it does. Just above the window, to the left.
TOM: Alright. Well, see, here’s what could be happening. First of all, I really don’t like the fact that you’ve got three 90-degree bends in this stovepipe. That’s a lot of resistance to kind of overcome. And also, with the three 90-degree bends, that pipe has lots of time to cool. And so the cooler the pipe gets, the more condensation you get. As the condensation forms inside the pipe, it basically washes down the pipe, comes out the seams of the pipe and carries away all of the charcoal debris that’s inside the pipe with it. So that’s probably the source.
And I guess what I would be more tempted to do – it’s not so much the kind of thing where you’re finding a leak. I’d be more tempted to replace my stovepipe with at least a double-wall pipe that was insulated. Because then you’re not going to have that difference in temperature and it will – you will never have any of those kinds of condensation issues. And it’ll be a lot safer, too.
My concern with that pipe is it’s really hard to clean and every time you have a 90-degree bend in a pipe, William, that’s equivalent, resistance-wise, to 20 foot of straight pipe.
WILLIAM: Wow. So I might be better off just running that thing straight up through the roof rather than taking it out the side of the house.
TOM: That’s the best thing to do, with an insulated pipe – a triple-walled, insulated pipe – straight up through the roof and out, without all those bends. Just make sure you’re following the National Fire Protection Association guidelines for this, get it inspected. And I think you’re going to be a lot happier with it.
William, thanks so much for calling us at 888-MONEY-PIT.