Temp < 10 F = draft that goes backwards when the door is open.

[woodpile]

Hi all,
The weather in the Chicago area has been staying in the single-digits of late, and my otherwise perfect draft is not so perfect. This evening's fire got the stove up to about 250 F before I had to feed it more kindling. When I opened the door, smoke came in after about 5 seconds. I keep my furnace thermostat at 45 F when I'm not home, so I assumed the draft problem was because the room air was too cold, so the cooler air drawn up the flue with the door open was not buoyant enough to maintain a draft. I used the furnace to get the house up to 60 F, at which point the same thing happened when I opened the door. I do not have any smoke coming out the air intake when the door is closed. The stove is a Lopi Answer set in my fireplace. The house is 2 stories, making the chimney about 20' tall, which is masonry, clay tile flue and on the outside of the house. I don't remember ever having any draft problem. Is there any way to work around this? Right now I'm not getting much heat from my stove and I can't open the door to build a better fire.

Thanks,

Scott

 

[begreen]

You have a cold exterior chimney. It will take patience to get it warm enough to start drafting well.

How is the stove terminated? Is there a full stainless liner or a short stub of pipe up past the first tile in the chimney?

 

[woodpile]

I have about 8' of 6" steel stove pipe up the chimney, then just the clay flue.

 

[begreen]

If you can install a full length, insulated 6" stainless liner in the flue it will behave much better.

 

[jtp10181]

What size is the clay tile flue?

 

[woodconvert]

The house is 2 stories, making the chimney about 20' tall, which is masonry, clay tile flue and on the outside of the house. I don't remember ever having any draft problem. Is there any way to work around this? Right now I'm not getting much heat from my stove and I can't open the door to build a better fire.

A) are you sure your chimney or cap isn't plugged?
B) are you sure your wood is seasoned?
C) if you have a clean out door on the outside of the chimney...is it closed?

If your chimney or cap is not plugged and your wood is good and seasoned then you shouldn't be having a problem unless you are getting a freak wind. When you start a fire in a exterior masonry chimney you may need an excess of kindling and small splits. I have a similar setup with an exterior masonry chimney and it can take an hour plus to get heat into that chimney and get some decent stove temps. That said, I've never had a situation where I could not get an immediate draft going unless there is a problem.

 

[velvetfoot]

I get reverse draft when everything gets cold, but as soon as I warm things up with newspaper & kindling and open an adjacent window a little.

 

[woodconvert]

Yeah, if your house is that air tight you would have a problem establishing a draft. That's easy to check...try to start it with a window cracked.

 

[begreen]

All good suggestions. If the wood is good, and the chimney cap is not plugged try this:

Create about 6 balls of rolled up newspaper. Put them in the stove, light and close the door so that it is only slightly open, maybe 1/2". That should reverse the draft. If not, repeat again. When the draft has reversed start a fire with very dry kindling and only small very dry pieces of wood (less than 1" thick). Leave the door ajar about 1/2". Continue to add larger pieces as the fire takes hold and close the door when the larger (1-2" thickness) pieces start burning well. Add larger splits as these start to burn down, but be careful not to smother the fire.