Pipe in Thimble Sloping Downward - Can I fix this myself?

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NHfarmgirl

New Member
Dec 20, 2013
19
Plaistow NH
Hello and thanks in advance for any advice. So heres the story, chimney was installed last year. I had it installed straight out the back a vintage Jotul 8 in nice condition. The pipe goes straight up about 30 feet. Worked beautifully for a year - once in a while had to heat up the stove pipe with paper to get it going but besides that burned like a dream. Fast forward a year someone recommended a damper and being the newbie I am did not know you cannot do that with a pipe going straight out the back. Smoked like crazy so replaced with new pipe with no holes and now it is smoking like crazy. After having the chimney cleaned and inspected and trying to figure out what the heck the issue is I took a short level to the pipe that starts from the wall and goes out of the house I believe its called the thimble. It has a really bad downward slope - the bubble goes all the way to the left when looking at it from the right side. The pipe coming off the stove is fine - coming up about 1/4" for 18". Can anyone recommend how I might fix this myself? I'm quite handy but I'm at a loss here...Ive spent $175 on the chimney sweep and would love to fix this myself. Thanks again for any advice.
 

Nick Mystic

Minister of Fire
Feb 12, 2013
1,130
Western North Carolina
I think you might get a better response if you post a photo or two of your problem. Your description is confusing to me. You first say that the chimney pipe goes straight up 30 feet, but then you mention a pipe coming out the back of your stove and it sounds like a second pipe that also runs horizontal, which you are referring to as the thimble. A thimble is just the hole through the wall that runs into a flue of some sort. It sounds like you are saying you have a pipe connected to the thimble and this pipe runs horizontally outside the house to your new chimney. If I'm reading things correctly, then you aren't likely going to be able to change the angle on this horizontal run without making an adjustment to your chimney. If you have a Class A chimney running up the side of your house it would seem you would need to raise the entire chimney up enough to get the horizontal pipe sloping downward toward your thimble instead of sloping in the opposite direction you describe it as sloping. If I've understood you correctly (pictures would make things clearer) then either your thimble would have had to move upward in your wall, which is very unlikely, or your support bracket holding up your chimney would have had to slip downward to change this angle. Lifting a 30 foot chimney back up in place would be a rather involved job. Maybe others will read your question differently and have other ideas. Good luck.
 

tcassavaugh

Minister of Fire
Jan 10, 2010
1,049
Southern Maryland
Welcome to the forum, there is a wealth of info here from relatively new folks and old sages. Both bring a wide range of experience to help guide you through any question. it sounds like you blame the installation of your damper for your issue....or at least a little. not likely. BTW, you can put a damper in a pipe going straight out the back, especially if you have a good draft. I agree with Nick, its a little confusing but it sounds more like its a draft issue. the starting or using some paper to get the draft going is an indicator that there might be a slight problem. being a newbie, the key damper didn't have to be closed but could have been adjusted to help control the burn. if done correctly, it still allows the smoke to flow. when I completely close my dampers (handle parallel with the floor) I get a little smoke spillage so I leave it cracked or open just a little to help promote a longer burn.

the angle to the thimble shouldn't be a problem unless its really severe. up is better than down but if the draft is good and pulling, neither would be a real problem. with the pipe in the stove, level isn't really a problem either. you mention you had a chimney sweep clean the pipe in an attempt to fix the problem. how long ago was that? I ask because the next question is how long have you been burning since and how long has the wood been seasoned. hate to go there, but its a critical factor. green wood can cause the creosote which in turn gums up the works and slows or interrupts the draft. the other thing is that maybe the air flow is gummed up on the stove. just a thought.

don't go spending a bunch on leveling your pipes.....try and figure out what is causing the draft problem. jmho

hopefully some other folks will enter the conversation and shed further light on the issue.
good luck
 

NHfarmgirl

New Member
Dec 20, 2013
19
Plaistow NH
Thank you, here are some picture to help clarify. So it is the pipe that runs from the wall to the chimney. The pipe from stove to wall was fine as far as slope. I figured it might mean moving the whole chimney - I'm just confused as to how just taking the pipe off and on a couple times could cause this colossal problem.

stove1.jpg stove2.jpg stove3.jpg
 
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NHfarmgirl

New Member
Dec 20, 2013
19
Plaistow NH
Very interesting... I had the chimney cleaned after the smoking issue - had a chimney service come out and that was his only suggestion. I'm burning from the 3 cords I had here since delivery in September. Burned it for a couple months and it burned really clean. Thats good news about the damper - because I think it would help alot with keeping the heat in the house instead of up the pipe. All I can say it is like someone hit a switch after I played around with the putting the damper in. So smoky I cant get a fire going without it smoking up the whole house. As far as heating up the pipe - only had to do that a handful of times with newspaper when I let the fire go out for a while. Thank for the reply.
 

Nick Mystic

Minister of Fire
Feb 12, 2013
1,130
Western North Carolina
You didn't actually post a photo showing the horizontal pipe you say is sloping downward to the chimney. You said you put a level on it to make this discovery. Did you put the level inside the thimble you show in the first photo and stick up against the pipe inside to determine this? How about posting a photo of the bottom of your chimney so we can see how it is sitting on the bottom support bracket. If the pipe angle through the wall changed since the original installation last year then either the wall thimble had to shift upward or the chimney support bracket had to shift downward lowering your entire chimney in the process. Either of these scenarios are possible, but seem unlikely to me unless you had a real shoe maker job done with the installation! As tcassavaugh mentioned, it sounds more like a draft problem. Have you looked at your chimney cap with some binoculars to see if it is clogging up with creosote. That is often the culprit when a stove has been burning fine and then starts dumping smoke out the door while reloading.
 

tcassavaugh

Minister of Fire
Jan 10, 2010
1,049
Southern Maryland
it looks like a good connection to me. the level, up or down, shouldn't be a problem. here's a thought......the bottom of the chimney pipe, or the " T " has a double cap on it so you can clean it (or at least mine does). have you checked to make sure the inner cap is still on? it might be possible that it became disconnected. mine had a small screw to hold it on but became a pita to find the hole again so I left the screw off and the lower cap will occasionally drop down inside the chimney pipe. that might cause a draft problem.
the only other thing I can suggest is make sure the direct connection to the chimney is ok. almost mentioned the cap thing like Nick...worth a check.
 

NHfarmgirl

New Member
Dec 20, 2013
19
Plaistow NH
Nick its the pipe in the first picture. I put a level on the bottom of the pipe and thats how I got the reading. Here is a picture of the bottom of the chimney.Going to take the cap off right now and take a look, going to hunt down the binoculars :) Thanks!
stove4.jpg
 
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tcassavaugh

Minister of Fire
Jan 10, 2010
1,049
Southern Maryland
one other thing, after looking a little more at the connection. the pipe inside the thimble looks like it might not be quite flush or tight (top of the pipe). make sure that when you connect, the connector pipe is fitted well inside for a good positive connection. you might be losing a little draft there.
 

begreen

Mooderator
Staff member
Nov 18, 2005
96,253
South Puget Sound, WA
Also make sure the Tee cap is on correctly and sealing well.
 
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Nick Mystic

Minister of Fire
Feb 12, 2013
1,130
Western North Carolina
I see what tcassavaugh is saying about the pipe inside the thimble making a gap up top. You definitely want to make sure you have a good positive connection between your stove and that pipe or you will be shooting flames, or at least extremely hot gasses, straight into your wall cavity! I haven't worked with a pipe and thimble arrangement like yours. It looks like it would be tricky hooking a connector onto it since it is recessed inside the wall the way it is.
 

NHfarmgirl

New Member
Dec 20, 2013
19
Plaistow NH
Nick what should I be looking for when I take off the cap? Cap was on tight with 2 screws tcassavaugh but once I took it off even with a flash light all I see is black - probably not a good sign. I dont know if this helps at all but I took a pic with my camera it only shows the first couple feet of pipe. thanks.
 

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NHfarmgirl

New Member
Dec 20, 2013
19
Plaistow NH
I see what tcassavaugh is saying about the pipe inside the thimble making a gap up top. You definitely want to make sure you have a good positive connection between your stove and that pipe or you will be shooting flames, or at least extremely hot gasses, straight into your wall cavity! I haven't worked with a pipe and thimble arrangement like yours. It looks like it would be tricky hooking a connector onto it since it is recessed inside the wall the way it is.

Yes it is tricky...the pipe from the stove fits over it and overlaps it by about a inch. good point.
 

WiscWoody

Minister of Fire
Dec 24, 2011
2,046
Winter WI
I put a damper on my EPA stove piping but it only caused draft problems so I removed it and my stove and I have lived in perfect harmony since! Lol. Does your stove have a primary air control on it? I have heard that's the only way you should control the stove if it does. You have a lot of stack height so you should pull a nice draft. Are you running any exhaust fans in the house? Ie. fart fans, a dryer or a often running hot water draft inducer maybe. But with your smokin' chokin' blokin' coinciding with the install of the damper I'd nix it. Even when it's 100% open it will slightly restrict smooth draft flow. IMHO....
 

Nick Mystic

Minister of Fire
Feb 12, 2013
1,130
Western North Carolina
NHfarmgirl,
I was talking about your chimney rain cap as a spot that could get clogged with soot and creosote and affect your draft. Many rain caps have a wire screen of some sort wrapped around the top section and this gets caked up with creosote if you burn wet wood. That is what you would look at with binoculars from the ground to save a trip up on the roof to inspect it. The photo you posted looks like it is looking up your flue from the bottom of the T- connector. Is that correct? If so, your flue doesn't look too bad down at the bottom. It's the top that usually gets more creosote built up on it since the flue gasses are so cool by the time the reach the top of the chimney they condense on the inside of the pipe and rain cap.
 

NHfarmgirl

New Member
Dec 20, 2013
19
Plaistow NH
I put a damper on my EPA stove piping but it only caused draft problems so I removed it and my stove and I have lived in perfect harmony since! Lol. Does your stove have a primary air control on it? I have heard that's the only way you should control the stove if it does. You have a lot of stack height so you should pull a nice draft. Are you running any exhaust fans in the house? Ie. fart fans, a dryer or a often running hot water draft inducer maybe. But with your smokin' chokin' blokin' coinciding with the install of the damper I'd nix it. Even when it's 100% open it will slightly restrict smooth draft flow. IMHO....

I took it out after all the issues and just put a new pipe in...I would love to live in harmony with my wood stove lol. The only air control it has is the draft wheel on the Jotul 8 which opens and closes varying degrees to let air in. No exhaust fans running at a significant rate. But I'll look into it. Thanks!
 

NHfarmgirl

New Member
Dec 20, 2013
19
Plaistow NH
NHfarmgirl,
I was talking about your chimney rain cap as a spot that could get clogged with soot and creosote and affect your draft. Many rain caps have a wire screen of some sort wrapped around the top section and this gets caked up with creosote if you burn wet wood. That is what you would look at with binoculars from the ground to save a trip up on the roof to inspect it. The photo you posted looks like it is looking up your flue from the bottom of the T- connector. Is that correct? If so, your flue doesn't look too bad down at the bottom. It's the top that usually gets more creosote built up on it since the flue gasses are so cool by the time the reach the top of the chimney they condense on the inside of the pipe and rain cap.


aaah okay I'll take another look. yes that correct. Picture taken at the bottom of the t-connector.
 

tcassavaugh

Minister of Fire
Jan 10, 2010
1,049
Southern Maryland
Nick what should I be looking for when I take off the cap? Cap was on tight with 2 screws tcassavaugh but once I took it off even with a flash light all I see is black - probably not a good sign. I dont know if this helps at all but I took a pic with my camera it only shows the first couple feet of pipe. thanks.
..........that's not too bad, I've seen worse. long as you have it off, you might as well run a brush up it if you have one. nick is right about the cap on the top of the chimney, if its clogged, it can definitely slow down the draft. jotul is a pretty simple operating stove. I've had two and still burn one and draft within the stove was never a problem. its likely someplace in the connection....pipe to chimney.....chimney cap.....bottom covers. that's all I can think of that would cause the problem.
 
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begreen

Mooderator
Staff member
Nov 18, 2005
96,253
South Puget Sound, WA
I would expect you would see a ring of light at the top coming around the cap but the camera may not catch this. If it is truly black up top it could be the cap screen is plugged.
 
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WiscWoody

Minister of Fire
Dec 24, 2011
2,046
Winter WI
You can see brush marks inside of the pipe so you know it was brushed like you said. I'd think he would have checked the cap too. Ive never seen one with a screen, just baffles but it doesn't hurt to check the whole shabang. If you've done all of this so far you are pretty handy. Buy a brush and extensions at the local home center store and jeepers cut out the sweepers charge.
 
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tcassavaugh

Minister of Fire
Jan 10, 2010
1,049
Southern Maryland
I would expect you would see a ring of light at the top coming around the cap but the camera may not catch this. If it is truly black up top it could be the cap screen is plugged.
good point......especially looking from the bottom up.
 

NHfarmgirl

New Member
Dec 20, 2013
19
Plaistow NH
So I was able to get a picture from a ladder on the opposing wall of the house of the top of the chimney cap. How can I tell if its clogged just from looking at? Again apologies I know this is probably a very basic question but I dont recall what it looked like before... As you can see more snow for New Hampshire this afternoon.

chimneycap.jpg
 
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