Water dripping from chimney
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Is it possible, that rain water or snow is getting via cap? My wood is well seasoned. Don’t believe this would be condensation....
JRHAWK9
Minister of Fire
water is a byproduct of combustion. It very well could be the water vapor in the flue gasses are condensing as soon as it hits that cold pipe.
brenndatomu
Minister of Fire
I went with my brother to look at a new OWB Friday night, it is a gasifier that runs very low exhaust temps (90* over water temp set point, when running WOT, and a good bit less when on standby) These units burn very clean and all you ever see is steam out of the chimney...and some clear water dripping out the bottom of the chimney. (its not sealed well there, on purpose)
The designer/owner was telling us of a customer that called in the first winter after he installed his new unit and he was complaining of "no heat". He was located close enough to the factory that they sent a guy out to look at it...they found that the customer had put the boiler under a metal carport, and rather than run the chimney up through the roof, like most do, he ran a pipe horizontal out the side...for about 10'! What they found was that the chimney pipe was full of ice...except for about a 1" hole!
Not that any of this directly applies to OP's problem...
The designer/owner was telling us of a customer that called in the first winter after he installed his new unit and he was complaining of "no heat". He was located close enough to the factory that they sent a guy out to look at it...they found that the customer had put the boiler under a metal carport, and rather than run the chimney up through the roof, like most do, he ran a pipe horizontal out the side...for about 10'! What they found was that the chimney pipe was full of ice...except for about a 1" hole!
Not that any of this directly applies to OP's problem...
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When I cleaned the pipe sometime in Dec., I had a hard time opening the clean out. There was about 1 1/2 “ of ice at the bottom of the clean out. I found that odd too. I had to chip that ice out
I was just curious which stove was hooked to that pipe. That dirty ice seems to hang off my cap occasionally. Same weather conditions. Very cold. Windy. Sometimes worse with active snow. In the past I have had water drip back into the stove and hiss as it hits the hot steel around the bypass plate during that weather. Guessing wetter wood may contribute.
In your case it appears to be condensing in the outside pipe sections, filling the cleanout and then finding that joint.
Highbeam
Minister of Fire
Your chimney is cold and your steamy flue gasses are condensing and running down. You’re lucky that the water has a place to go other than in a puddle inside your home.
Running hotter flue gas temperatures would solve this. Just because the BK can run so low that it becomes a condensing appliance doesn’t mean you should. A second option would be an insulated chase around the pipe.
I don’t suppose you’re interested in converting to an all vertical interior chimney system.
I would be awfully tempted to poke a 1/4”’hole in the bottom cap of the clean out tee. Keep it clear to allow drainage.
Running hotter flue gas temperatures would solve this. Just because the BK can run so low that it becomes a condensing appliance doesn’t mean you should. A second option would be an insulated chase around the pipe.
I don’t suppose you’re interested in converting to an all vertical interior chimney system.
I would be awfully tempted to poke a 1/4”’hole in the bottom cap of the clean out tee. Keep it clear to allow drainage.
This is the last thing I want hear. Thank you however. Do not have that issue with the VC (had to put this out there).
Highbeam
Minister of Fire
Low efficiency stoves and higher burn rates puke more heat up the stack. Both flow rate and temperature.
What would that do? Condensation would just drip back into the stove lowering the flue temp and creating more creo? I am sure I am not the first one with this predicament.
JRHAWK9
Minister of Fire
Lots. With these more efficient wood burning appliances comes reduced flue gas temps. Having an insulated interior chimney would keep the temp of the pipe warmer so the flue gasses would be a lot less likely to condense in the first place. It's the main reason why I chose to keep my chimney almost all inside my heated space. I have a 34ish foot chimney and all but the last 5' or so is outside.....which is the part sticking up through the roof.
I have a barometric damper installed in which I have an outside air kit ducted to it, so it is taking in cold outside air to regulate the draft instead of air inside the heated space. My flue gas temps get down to about 300° right at the furnace exit....add to that the mixing in of the cold outside air from the barometric damper. I could not do this if I had an uninsulated outdoor chimney, as my flue gasses would probably be condensing and would be dealing with the same issue you are.
Like I said before, you are not going to eliminate water vapor in your flue gasses....it's part of burning wood. You just need to make sure your flue gasses are kept warm enough so the water stays in vapor form until it exits the chimney.
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Running the chimney straight up thru the interior of the house will keep the flue gases much warmer, thus avoiding the condensation. That will also help the flue stay cleaner and it will improve draft.
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