Have a new problem with my 4 year old stove.

Hello all ! Am a new member here but have learned a ton from this site over the years. I never bothered to register and post here, cause I could always find what I needed by searching the forums on my own. However.......

I have a Century Hearth non-cat wood stove. I installed it myself 4 years ago and have loved the stove, and had ZERO problems till about 3 weeks ago.

It has started smoking into the house a little bit when I open the door to add wood. This has gradually gotten worse and worse over the past few weeks. Now it's to the point that whenever I need to add wood, it smokes up the house bad. After I add the wood and shut the door, it takes a long time to catch-up so I can shut the air off... and then it doesn't burn like it should. The smoke is just not leaving like it should.

I have checked my flu, and it is clean as a pin , with zero build-up. The pipe from stove to thimble is clean. And the thimble is clean.
My wood is ALL hardwood, and has been cut , split , and stacked in the dry for at least One year.

Today, I let it burn out and cool down so I could take it apart. I pulled the pipe off the stove and looked into the top of the stove. It had some very fine ashes built-up about an inch deep across the top of the burn chamber. So I cleaned it all out and re-attached the pipe.

I built a new fire, and had to keep the house doors open for 30 mins to let the smoke out. (this is unusual for this stove even with a cold flu) It seems that the smoke just doesn't want to leave the burn chamber thru the flu. It just hangs out and takes it's sweet time leaving the stove. After the stove got up to 600* and was burning good, I opened the door a few inches to test it out, and not only smoke came into the room, but flames were shooting out the door and up over the top of the stove.


Like I said, I've had this stove for 4 winters now, and this has never happened before. What the heck is going on here ? I'm baffled.

It's a masonry flu. roughly 32 feet tall.

yesterday, I climbed up on the roof and removed the cap (which is clean) and shined a 2 million candlepower spotlight down into my flu. All is spotless. And I resealed my cleanout door with silicone cause I thought that could be causeing the bypass you suggested. .. but no change.

Thanks for the fast replies... and keep the suggestions coming... It helps with the troubleshooting process.

House Door being opened or closed seems to make no difference.

And I haven't made any changes to the house HVAC or added any vents, or changed windows.

Will try replacing my pipe from stove to thimble and re-sealing the joints to see if that helps.


This is starting to bug the heck outta me... Why is this just starting for no apparent reason ?

offroadaudio said:

It is weird that this just started. If you don't find an answer easily, you could always reline the entire chimney.
Probably not what you're looking to do since it worked in the past, but I think most here would agree that it would solve the problem by resizing the flue properly.
For a self install it might cost you around $500 give or take.

Click to expand...

Why after 4 seasons of flawless performance, would my flu suddenly be the wrong size ? Not to say I am un-opened to the idea of lining... but this would have to be an absolute last resort.

This is not just a little bit of smoke coming into my house.... I woke up this morning and thought the damn house was on fire. Ran to the basement and the wife was just adding 2 sticks of wood to a bed of coals. That was at 8 am and it's now 9:30 and I still don't have all the smoke out.


Dam$Mut#3Rf09^3R WTF

I'm sittin in my living room with the doors and windows opened and it's 25* outside. Keep the ideas coming guys... I gotta fix this shiv

offroadaudio said:

This REALLY sounds like a clogged flue!

Click to expand...

I agree... I was sure that was my problem. But I opened my cleanout and stuck a hammer in there. then shined a spotlight down into the flu from the top... and could see my hammer easily. The flu is surprisingly clean... It is grey but I can still see the mortar joints in the clay liner.

8x8

Have been thinking about this more.. The start of the burning season started out just fine... It is just the past month or so that has been the problem... Hmmmmm

Hey ORA , what are the environmental conditions that you mentioned above that could be happening here ? I gotta start looking at that end of spectrum. My equipment is good , and no changes to the house, so now what ?

I'm thinking I'm gonna temporarily attach a flu extention and see if that fixes problem.

( more info about flu )

It is roughly 35 ft tall and on the north side of the house. Has worked fine for 4 seasons , BUT ... This has been a very consistently cold winter here, with many days in a row, at or below freezing for the highs , and down in teens and single digits at night.

Could it be that the flu is just not able to maintain the temp it needs to draw efficiently this year ??? I NEVER let the stove go out when it's cold weather. I'm self employed and work from home, so I always maintain a nice hot fire . It is rare that the magnetic temp ga. reads below 200*....and that is usually in the mornings when I first get up.
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