Problem with draw after replacing chimney cap (problem solved!!!)

[golfandwoodnut]

I have had an issue with an improperly installed chimney cap for quite some time. As you can see in the picture the installer did not properly seal the cap and I was having extreme heat loss up the chimney. However, the chimney drew very well. I also did not like that the chimney requires about a 40 foot ladder that I did not have and the cap was difficult to keep the screen clean. So I opted to get a more traditional cap as you see in the other picture and properly seal the cap and insulate with Rock Wool at the top. I had a heck of a time finding a sweep or installer who would come out so I hired my window washer to go up and install it. I was thankful that he did but I have been having a problem when I open the door on the stove that I often get back puffing and I know the cap is brand new. I ran the sooteater up to be sure the chimney was clear. Is there a big difference in the type of caps or could the window washer have done something to foul things up. It is frustrating.

 

[webby3650]

The only thing I could think of, is maybe the flex runs too far up into the new cap? It's kinda odd to have problems with keeping the cap clear with a Jotul or any high end stove, is your wood dry?

 

[embers aplenty]

Not trying to be the barrer of bad news but If it's been a month or two since installing the new cap, you might need to check just the cap again. Sometimes the small holes can stop up some what faster then you might think which at times can cause what your experiencing.

Has happen to me before. Chimney can be clean but the screen part of the cap can be gummed over enough to cause the back puff. Otherwise, you may have an air leak somewhere, probably at a pipe connection point. Just my.02.

 

[golfandwoodnut]

I do not believe it can be either one of these issues as I am way ahead on wood and my supply is very dry. Same wood I was burning with no issues. Also the problem happened right away with the new cap.

 

[webby3650]

The only thing I could think of, is maybe the flex runs too far up into the new cap? It's kinda odd to have problems with keeping the cap clear with a Jotul or any high end stove, is your wood dry?

 

[pen]

If you just did this in the last few days I know the temps here in NEPA have been quite warm and believe they have been in your area too. If that's the case, warm weather can certainly change your draft.

Otherwise I'd check what web suggested and make sure that liner doesn't stick up into the cap too far.

Only other thing I can think of would be if this style cap somehow is negatively effected by the way the wind moves over your house, and the design of your old cap prevented this issue.

pen

 

[embers aplenty]

My cap is about the same as your old one. I don't get any back puffing unless cap is dirty. I wonder if since you have a more open style cap, now, that it might make it easier to get a down draft now?? Just trying to help.

I can see why the first cap didn't stay on, the flange is just for a flat top masonary chimney like I use instead of for a terra cotta deal, which is what yours looks to be.

You've probably tryed opening up the air controls and cracking the stove door a few minutes before opening it. If not, that wouldn't hurt to try. Iduno, just trying to help. I know that can be agravating. My wife sure gets on my can if I smoke the house up. :smirk:

 

[webby3650]

My cap is about the same as your old one. I don't get any back puffing unless cap is dirty. I wonder if since you have a more open style cap, now, that it might make it easier to get a down draft now?? Just trying to help.

I can see why the first cap didn't stay on, the flange is just for a flat top masonary chimney like I use instead of for a terra cotta deal, which is what yours looks to be.

You've probably tryed opening up the air controls and cracking the stove door a few minutes before opening it. If not, that wouldn't hurt to try. Iduno, just trying to help. I know that can be agravating. My wife sure gets on my can if I smoke the house up. :smirk:

That old top plate was fine, it just needs some insulation stuffed around the liner and siliconed down.

 

[Locust Post]

That new cap is the same cap I installed when I put my liner in this year. My liner is cut flush so nothing showing through the mesh. I get a wonderful draft. Pen may be on to something with the way the air hits your chimney and the warm temps now. When you say back puffing is this in the middle of a good burn,early in a load or just about any time the door is opened. Just wondering if it is a difference in draw and when a large amount of air rushes in is this causing the issue. I would see how she does when we get some cooler weather again.

 

[embers aplenty]

My cap is about the same as your old one. I don't get any back puffing unless cap is dirty. I wonder if since you have a more open style cap, now, that it might make it easier to get a down draft now?? Just trying to help.

I can see why the first cap didn't stay on, the flange is just for a flat top masonary chimney like I use instead of for a terra cotta deal, which is what yours looks to be.

You've probably tryed opening up the air controls and cracking the stove door a few minutes before opening it. If not, that wouldn't hurt to try. Iduno, just trying to help. I know that can be agravating. My wife sure gets on my can if I smoke the house up. :smirk:

That old top plate was fine, it just needs some insulation stuffed around the liner and siliconed down.

Good deal. He might want to go back to it, if it worked good. Not a mason here. just looked like a flat flexy flange wouldn't adhere to that thin flanged terra cotta, but I guess it would. Cheers!!

 

[Hogwildz]

Chances of sealant holding that old cap on alone are slim. Ideally, the cap's base should have 90 degree flanges on all 4 sides to wrap down onto the sides of the clay. The can be secured by carefully using anchor screws.
As far as draft, I see no reason why the new cap should not perform as well as the old. My vote is the liner is prolly damn near up to the inside bottom of the new cap top.

 

[embers aplenty]

Chances of sealant holding that old cap on alone are slim. Ideally, the cap's base should have 90 degree flanges on all 4 sides to wrap down onto the sides of the clay. The can be secured by carefully using anchor screws.
As far as draft, I see no reason why the new cap should not perform as well as the old. My vote is the liner is prolly damn near up to the inside bottom of the new cap top.

Sounds like a winner to me. Probably time to get back on the 40 foot ladder. That liner sticking up in the cap to far would sure do it. The old one popping off like that would make me think the liner was almost to long with it as well.

I feel much better knowing that my flange has silicon and tapcon screws holding it steady. Maybe a friend of a friend with a bucket truck? :coolsmile:

 

[golfandwoodnut]

Thanks for all the ideas. It is not the weather because it has been going on in different weather conditions. The problem seems to happen almost anytime I open the door the whole way. When I crack it, it is OK. I open the air flow the whole way and try to only reload on coals. But before, I never even had to be real careful. I may take the mesh out of the old cap and have it reinstalled. Just wondering if the installer could have cracked the flex liner or something. I would imagine it would be pretty tough to do that.

 

[pen]

Thanks for all the ideas. It is not the weather because it has been going on in different weather conditions. The problem seems to happen almost anytime I open the door the whole way. When I crack it, it is OK. I open the air flow the whole way and try to only reload on coals. But before, I never even had to be real careful. I may take the mesh out of the old cap and have it reinstalled. Just wondering if the installer could have cracked the flex liner or something. I would imagine it would be pretty tough to do that.

Hmm.

Tough to say w/out an inspection and as much as it sounds like it's unpleasant to do, I think you really need to take a good look at what he did. Hell, the guy could have cut the thing too short even and it fell back down into the chimney and the base of that cap is partially blocking it!

pen

 

[Hogwildz]

Just noticed, all the creo laying on top of the old top plate. And the size of those holes in the old cap screen..... shows me either two or both things....
1. Your wood ain't as dry as you think.
2. Your smoldering or not burning hot enough.
Thats alot of crap for burning good seasoned dry wood.

 

[mywaynow]

I think it is quite possible that the window washer did not act as a chimney sweep/technician. I would also lean toward the possiblity that the liner is not connected to the cap and has dropped into the chimney. Would a window washer have the tools and supplies to do that job properly, let alone the skill?

 

[Wood Duck]

My vote is you should go up there and look. Perhaps it is something simple and obvious. If you can identify the problem then you'll know what to describe to the fixer you hire to fix it.

 

[Burd]

Just by looking at your pictures I can tell you that your window washer didnt install it right. If you look at the old cap your flex liner is well above the clay. To install the new cap the liner needs to be cut down to fit the new cap.( Aleast six inch cut of the liner) Just look at were the hose clamp is. Its well above the clay liner. Could the roto router be sending that creo up and out the cap. Most likly there isnt any thing wrong with the old cap. I think it operator error with the roto router being sent up to far and pushing the cap off the clay. These liner have a lot of movement and my 2c is your new cap doesnt alow for play. Stay with what works and Find your self someone that nows what there doing.

 

[BrotherBart]

Call the guy that installed the new cap. Ask if he trimmed the liner. If he didn't, there is the answer.

 

[webby3650]

Chances of sealant holding that old cap on alone are slim. Ideally, the cap's base should have 90 degree flanges on all 4 sides to wrap down onto the sides of the clay. The can be secured by carefully using anchor screws.
As far as draft, I see no reason why the new cap should not perform as well as the old. My vote is the liner is prolly damn near up to the inside bottom of the new cap top.

I've cleaned dozens upon dozens of liners that had the plate siliconed down, and it's the way we install them, I have never seen one that was loose at all.

 

[golfandwoodnut]

I saw a stove installer today and he believes it is the type of cap. He had another Jotul that had the exact same problem and went with the round tall cap and it solved the problem. He is coming out on Feb 16 th and will do a sweep and reinstall the old cap without the wire mesh. As we discussed the only real fear is that a bird may go in. Let's face it the mesh will not stop a spark, or at least all sparks. I will know for sure by then and this way I can get a cleaning from the top and an inspection. Looks like I will be taking the original installer to the magistrate as this has caused me a lot of headache and he never came back as promised. Be sure your installer seals the cap with the proper silicone. My used none.

 

[Burd]

That liner was pushed up from the roto route witch Brooke the seal of the silicone most liner are meant to be cleaned from the top down. Just like
We install them. That liner lifted at least six inch

 

[golfandwoodnut]

Just noticed, all the creo laying on top of the old top plate. And the size of those holes in the old cap screen..... shows me either two or both things....
1. Your wood ain't as dry as you think.
2. Your smoldering or not burning hot enough.
Thats alot of crap for burning good seasoned dry wood.

That is an old picture(over a year and a half ago) and has nothing to do with the issue at hand. Also the fact that the chimney was not sealed caused even more condensation as normal and I hear this happening on a lot of caps no matter how seasoned the wood, especially on tall chimneys. That is why I am opting to eliminate the screen.

 

[webby3650]

That liner was pushed up from the roto route witch Brooke the seal of the silicone most liner are meant to be cleaned from the top down. Just like
We install them. That liner lifted at least six inch

That topplate had no silicone though, liners aren't designed to be cleaned any certain way, if installed properly, you can't push it up.

 

[golfandwoodnut]

That liner was pushed up from the roto route witch Brooke the seal of the silicone most liner are meant to be cleaned from the top down. Just like
We install them. That liner lifted at least six inch

There was no sign of any sealant used.