Condensation dripping inside new stovepipe -- is this normal?

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lllars

New Member
Oct 14, 2018
2
vermont
Hi, this is my first post here. We just installed 17' of 6" metalbestos stove pipe in our new construction house. I'm seeing what seems like a lot of water dripping down from inside the stovepipe.

I figured it was humidity from warm house air condensing on the inside of the pipe and underside of the chimney cap. So, I put a bag over the bottom end of the stovepipe to block airflow. But, we're still getting a lot of condensation. We collected maybe 1/2 cup of water inside the bag last night.

I haven't hooked up the wood stove or any single wall connector pipe yet. The 17' of metalbestos is a straight shot up through the roof, with 8' of the pipe exposed above the roof. It was fairly cold out last night, about 35F. Inside of the house is about 60F.

Is this normal? With the air flow blocked off, I have no idea where the water could be coming from. Any ideas?

Condensation dripping inside new stovepipe -- is this normal? Condensation dripping inside new stovepipe -- is this normal? Condensation dripping inside new stovepipe -- is this normal? Condensation dripping inside new stovepipe -- is this normal?
 
Saturday was rainy here, same with some friends in southern VT near NH. How was your weather?
 
Yes pretty normal when it has been as wet and humid as it has been this summer in the north east
 
The interior of the house and pipe is cooler than the warm humid air outside. This is causing a downdraft + condensation. It's the same principle behind desert water collectors. When the home envelope is heated this should not happen.
 
Fri night / Sat morning was rainy, then the rest of Saturday was just cloudy. Sunday was sunny.

We didn't get as much condensation Saturday night and Sunday. I think what happened is that we just got a ton of condensation inside the pipe before I blocked it off. I mean every possible spot must have had a droplet stuck to it. Then occasional temperature fluctuations or vibrations would cause the condensation to flow down the pipe. Shining a flashlight up there yesterday I could still see some areas with tons of condensation. We did have the chimney wide open with no blockage for a day or two and I think we just ended up with more water stored up there clinging to the walls of the pipe then I would have thought possible.

Well I finished installing the stove today and we had our first fire tonight (hooray!), so I won't be able to monitor the condensation quite so easily from here out. But I'll definitely report back if I see a lot of water leaking into the stove.

Btw, is there a good thread here for how to operate a wood stove efficiently? Or one dedicated to the nuances of a middle age VC encore? I dug into it pretty deeply yesterday, fettling things and replacing gaskets, and it seems to be working reasonably well, but some expert knowledge might be useful.
 

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