Help!! Horrible back drafting furnace

[maple1]

I don't know the maker... I will try to get a picture of it here shortly. Also, I should add that currently my ckeanout outside is open. I just talked to someone at a stove shop that suggested I cap that clean out off and see what happens. Fingers crossed that will work

And, as also quite often happens - a 'by the way' slip of the tongue a few posts after the OP reveals the issue in loud living color.

 

[Marshy]

To be honest, I'm not sure what the thimble is.

The part that goes through the exterior wall of the house. It is the horizontal connection to the chimney that is permanently fixed to the chimney.

 

[Lawson111]

Yea put that clean out cap back in. Is it a door or a plug type at the bottom of the tee that connects to the thimble( the piece that goes threw the wall) if it’s a plug/cap type that goes in the bottom of the tee mine has fell out before if I don’t tap it I’m will a hammer a little. There also should be little brackets that swing over when the plug is in that won’t allow it to fall out all the way. Well my Selkirk setup is this way not sure what brand chimney you have.

 

[Lawson111]

I am actually going to get some inside stove pipe to change my interior set up. I to have pretty much the same setup you have where it 90s out of the stove goes vertical for about a foot then another 90 and about 2feet of horizontal pipe. After reading everyone’s comments on the horizontal runs I’m going to eliminate one of the 90s and 45 it right at my thimble and run the pipe from the 90 that comes out of the stove at a angle. Hopefully this helps my draft and creosote buildup out. I have a little issue with draft and creosote buildup in the spring and fall when it’s a little warmer out.

 

[Hunter130]

Here is interior pipe in question

 

[cumminstinkerer]

Hunter130, not to be to critical but looking at the picture it looks like your thimble is either dead level or possibly reverse sloping, you really need to get the exit end ramped up as Marshy said a minimum of 1/4" per foot of run. More is always better of course, and like I posted earlier the only way you can really do that is to hog the hole in the block wall out and the cement it back around the pipe once you get it set where you need it.

 

[maple1]

That's a bit different than what I had pictured in my head from the description. Not sure you can change that setup much without moving the furnace, or shortening up that section of insulated stuff. I would likely try to work a T in there at the bottom, using one end of it for a cleanout - would make keeping things clean easier at least. Like, maybe, a T right off the furnace (pointing up & down with clean out cap on the bottom), then work in two 45's to replace the top 90. Sections of pipe in between to make things fit together.

Is that key damper closed though? Or partly? Hard to tell in the pic.

A pic of the cleanout & area would also likely be useful.

 

[Marshy]

The pipe between the stove and the thimble appears to be single wall black stove pipe. Your elbows are adjustible.

I would try this immediately:

Put the adjustable elbow on the outlet of the stove and put the other on the thimble. Adjust them so they align and connect them with a straight run of pipe. You may need to cut a straight section to fit to length.

You can buy single wall black stove pipe at nearly any hardware store. You will also need a good pair of tin shears.

The gasses will have enough velocity to over come the restriction of the thimble even if it doesn't have the proper slope of 1/4" per foot.

I would reuse the straight section you have in the middle, just ditch the straight section of oujt the backnof the stove and you'll need to add length to the middle. Simple.

 

[Lawson111]

Very similar to my setup and I honestly only have issues on warmer windy days. I am going to try and eliminate the horizontal run when it warms up around here and I can shut the stove off. But I would fix your cleanout issue and go from there first before you change all that. Doesn’t seem like you have a lot of options without a lot of work.

 

[sportbikerider78]

Doesn't seem like that much work to me to completely change that setup. Working with black pipe is crazy easy...and so is motar'ing that pipe back in place when he is done.

6 beer job...max.

 

[cumminstinkerer]

Doesn't seem like that much work to me to completely change that setup. Working with black pipe is crazy easy...and so is motar'ing that pipe back in place when he is done.

6 beer job...max.

agreed sportbikerider78, six beers, a hammer, a chisel, some mud, and a trowel all done

 

[Hunter130]

Thanks everyone for the help. I just picked up a cap for the clean out tee... upon cleaning I found that the interior single wall pipe was fairly dirty, the rest of the chimney was near spotless. As of now my therory is that the clean out was pushing cold air in resulting in a somewhat bottle up of smoke, resulting in creosote buildup in the interior single wall pipe. Also, I always run the key dampener wide open.

 

[maple1]

Seems to me this cleanout situation is still kind of fuzzy to us - a pic would help.

Running with an open cleanout would mean that the top of the chimney is pulling all its draft up through the cleanout. Meaning that the stove isn't seeing any draft. And that whatever smoke is making it into the chimney is being turned to creosote pretty quick. A double whammy.

I don't think you really need to do anything to the stove pipe that is there, if you simply get the cleanout blocked. If I am understanding the situation correctly. And I still might not be.

EDIT: I would likely change it up though, just to make it easier to clean, if nothing else, adding a cleanout T at the bottom. Also from an above suggestion - if going to the store to get some new pipe, I would get new adjustable 90's also. I never have any luck trying to adjust those things after they have seen some use. Sometimes even when new they sometimes don't want to adjust the way you want.

 

[Lawson111]

X2 on the new adjustable elbows. I just had to buy some to change my setup. Like maple1 stated after they get dirty there darn near impossible to adjust them.

 

[Hunter130]

Okay got my clean out cap and of course it doesn't fit It is for dura tech pipe and mine is dura plus. I can't even find dura plus caps alone online? One problem after another

 

[brenndatomu]

What happened to the old cap? They don't just blow away normally...

 

[Marshy]

X2 on the new adjustable elbows. I just had to buy some to change my setup. Like maple1 stated after they get dirty there darn near impossible to adjust them.

My experience with the elbows has been the opposite. Maybe because my stoves are pre-EPA and keep them clean. If anything they losen up and need replacing after 3 years or so.

 

[Marshy]

Very similar to my setup and I honestly only have issues on warmer windy days. I am going to try and eliminate the horizontal run when it warms up around here and I can shut the stove off. But I would fix your cleanout issue and go from there first before you change all that. Doesn’t seem like you have a lot of options without a lot of work.

Why people de code to install their chimney connector pipe like that baffles me. Thst horizontal run kills your draft. Its so easy, put the adjustable elbow at the wall and one on the back of the stove connect with a straight section of pipe. No double 90's and 3'of horizontal run. Sheeze. LoL

 

[maple1]

My experience with the elbows has been the opposite. Maybe because my stoves are pre-EPA and keep them clean. If anything they losen up and need replacing after 3 years or so.

Might come down to the quality of what's at your local store. We have basically the cheapest crappiest stuff here. I got one once that I couldn't budge at all, thought it was welded together. Must have been all pinched closed tight when it was put together. The stainless ones that were used when my boiler was originally installed in 1996 were great even 17 years later.

 

[Lawson111]

Why people de code to install their chimney connector pipe like that baffles me. Thst horizontal run kills your draft. Its so easy, put the adjustable elbow at the wall and one on the back of the stove connect with a straight section of pipe. No double 90's and 3'of horizontal run. Sheeze. LoL

It was my first wood stove and I set it up the same way my father had his and he never had an issues... but his chimney was also 30ft tall. I got the stuff to change it just got to wait until I can shut the stove off and change it. High of -10 here tomorrow

 

[Hunter130]

I'm not sure what happen to the old cap, I purchased the house 2 years ago and there has not been one since I've purchased the house

 

[Fred61]

They started installing thimbles with a slight angle toward the chimney back in the 70's when air tight stoves started to become popular in order for the dripping creosote to stay within the chimney and not flow out into the living space. A correctly built chimney should have no problem overcoming any loss of draft. It's not in there at so much of an angle so that the smoke has to go down. Some old time masons refused to do it because their fathers' told them that smoke had to go up.

 

[Fred61]

I'm not sure what happen to the old cap, I purchased the house 2 years ago and there has not been one since I've purchased the house

That's your problem

 

[Hunter130]

Alrighty guys, here's the verdict, I took apart the chimney, cleaned it very throughly, then added a redneck cap to the clean out T. The cap I bought (tractor supply crimped 6" cap) was slightly larger than my duraplus piping. Soo, I removed the cap from the crimped piece; and got it wedged up in there with a piece of steel; so I'm sure it's not 100% sealed up but is better.. now, I started the fire, had a small amount of smoke come out while starting (it was expected due to extreme cold) then once fire got started, it seemed to be all good to go. However, once I got a full load of wood in the furnace, it started smoking out the door again when you open it. Not just a light smoke but a kind of blow it in you're face. Still better than before, but not 100% yet

 

[jatoxico]

Aside from sealing up the clean out well since you have a basement install it may help to do some air sealing upstairs especially in the attic. Got a leaky set of attic stairs?


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