Help wood stove/chimney poor draft after 15 years

I have an Atlanta stove works Huntsman wood stove in the basement, connected through the block wall to Metalbestos Air cooled triple wall pipe, in a chase. The total height is about 15 feet. It meets the 3’ 2x10 rule.

The stove and chimney have been checked, and there is no blockage.

The fire does not pull like it should, it worked fine last year. When a fire burns with the air inlets open it will smolder and when the door is opened smoke backs into the house.

I am doing the same thing I have done for 15 years. I have had it looked at by 2 chimney services and they indicate a back draft problem, most likely caused by the increase of tree height over the last 15 years and recommended a Vaccustack. I did this and it did not help. ½ of some others I have talked to indicate a possible stove problem, and the other ½ indicate a possible chimney problem.

The bottom line I am getting from the installers is to try a new stove, if that does not work, then replace the chimney.

Any ideas on how to further try to determine the problem/cause will be greatly appreciated.

No, the last thing I did was finish the basement 10 years ago. Everything worked until this year.

We did get a new dryer and replaced a vent fan, but this happens when nothing is running.

One thing I did notice yesterday, is I am getting downdraft from the chimney. The stove has not been used for a while, and when I open the air inlet on the front and put a match in front of it it blows out. I never noticed this before because I never did it. Is this normal?

I have always nedded to clear the the flue before lighting a fire, but assumed the cold air was sitting in the chimney, not really blowing back down so hard. I thought once the cold air was removed the heat would continue to draft.

Update, I agree something has had to change, but I can not find any leakage. Maybe it was marginal to begin with and the addition of the trees getting bigger, basment finished, Radon system, new dryer, new vent system for central AC/heat vent unit, and house getting older ALL contributed to the final failure? I shut as much down as was possible to test, but with no luck.

I added 4 feet of Black stove pipe as a test, and it did seem to draft much better. without it there is definatley a down draft!

The problem is They do not make triple wall air insulated pipe anymore, and I have been told i can not add insulated pipe to air pipe. In addition the pipe is enclosed in a chase.

the only other solution, not an easy or cheap one is to add a draft fan at the top of the pipe. Has any one had any experience with this option?

Thanks for all the advise.

UPdate2

This has been driving me crazy, the coldest winter in 15 years and I can't burn my wood stove.

When I added 4 feet of black pipe to see if the increased hieght helped, it seemed to at first, but back to square 1 soon after the fire was light. The Radon system I have installed has been for 7 years, no problems until now.

After talking to a very knowledgeable gentelman from this board about the the backdraft/negative pressure situation I am one again leaning to the wood stove as the problem, not the flu. I have turned everything off, opend doors and windows and none of this works. This seems to indicate there is not negative pressure. I checked the top secondary burn chamber and made sure it is clean/clear, again and it is. The flu will draft at first when I light paper to clear the cold air, but I can not keep a fire lit.

I used a Surefire light in side the stove and discovered a slight breach in the system where the secondary chamber sits on top of the stove. I have never seen any smoke leak from it but I can see light coming through. The only thing i can figure is there is enough of a leak that causes the system to not be tight and draft like it should. I am going to try to get some wood stove cement and seal it and see if that helps.

any more ideas let me know, I am willing to try anything.

Update3

I sealed the small are where the possible leak was. I am not sure if it was my imagination, but the stove seemed to light/burn better, for a little while, then it started to die out again!

Its hard to believe the stove started leaking that bad over the summer, to the point where it won't draw, but no visible leaks.

Back to square 1, can't keep a fire burning. The only options I see at this point are:

1 Try a fan on the top
2 Try a Draw Collar
3 try a new stove, if that does not help
4 try a new chimney

Does anyone have any experience with either the fans on top of the chimney or the draw collar? Since this worked for so long either fix kinda sound like a bandid fix, but??

Options 3-4 are the most expensive, and 4 is also a lot of work! Not sure if it is Worth it?

At this point I really don't know what to try. The other thought was to wait until warmer weather, take the stove outside and use black pipe to connect a chimney of the same specs as the one I have. If it burns properly that would indicate a chimney draft problem, if not a stove problem??

As always any other advise

Thanks

Update 4

I sealed every seam on the stove and tried to light a fire again tonight. Same results.

In any case I am no longer able to use the wood stove. I just can't imagine the stove is still leaking so bad after I sealed it to prevent the system from drafting. I am really starting to think the problem is with the chimney. I do notice a pretty strong down draft, and it is harder to clear the flue than I ever remember, so down draft or negative pressure may be an issue. It is just hard to believe the system worked as well as it did for over 15 years, then all of a sudden it does not work at all.

I have T with a clean out on the bottom where the thimbel goes through the wall block wall in the basement. I can not get to it because it is enclosed in a chase, but I can tell it is still on, I am just not sure if it is loose. I would think if it is loose, and not air tight that would effect the draft ?

I keep going back and forth as to the possible cause, but if it was a negative pressure situation wouldn't open ing the basement door, window and shut down the radon system eliminate the problem ?

Any one use a fan, like the exhausto ?, it may be cheaper then tearing out the chase and a new chimney.

Any ideas?

thanks again.