Cold Chimney Syndrome

[jeffs]

Have been battling classic "cold chimney syndrome" with our new wood stove.
I've read a few suggestions, just wanted to bring it up again, and see if there were any fresh ideas out there?

Our setup–
Napoleon 1900, sits in basement.
Flue is single wall pipe, goes up about 2', takes a 90 degree elbow, runs about 2 feet to thimble.
I have a 1/4" rise per foot in the horizontal section.
Brick chimney is exterior, with new SS insulated flex liner.
Chimney extends height of 2 story house plus about 3 feet above the peak.

When starting I've tried the newspaper trick, but without a direct route to the flue, the smoke just pours out the front.
I tried sticking a Pelonis heater in the stove for 20 minutes prior to startup, didn't seem to make much difference.
Have tried doing this with a nearby window open, didn't make any difference.

My next attempt will be a propane torch to preheat the stove for a couple of minutes, or a piece of a fire-starter log.
I've also seen the suggestion to replace the 90 elbow with a 45/diagonal pipe/and second 45.

Any other suggestions?

 

[shawneyboy]

Top down with good dry wood or warm her up with kindling only, then go bigger.

 

[jeffs]

What do you mean by "top down"?

I am using very dry wood, starting with a little newspaper and very dry kindling, then slightly bigger, then slightly bigger.

 

[mellow]

You need to warm that liner, don't think the little bit of heat you have tried so far is doing the job in these temps, if nothing else works try sticking a hair drier into the thimble to warm up that liner and get a positive flow going.

 

[jeffs]

I'd have to disconnect my pipe (which is screwed together per specs) every time I start a fire to get into the thimble.

 

[mellow]

You could try removing the top baffle in the stove and jerry rig a support for the hair dryer to blow up the single wall pipe and hope that hot air will reach the liner, even with it insulated that liner is still cold.

 

[raygard]

I use one of those plumbers MAPP Gas canisters from Home Depot or lowes. You know the ones. Looks like a 14" high Oxy/Acetelene bottle with a pistol grip nozzel. I've learnt that if I have a cold chimney I am going to have smoke rolling out of all orifices of the stove. So I fire up my little Creme brulee Bottle and fire it for 60seconds through the opened damper in the stove and into the stove pipe. The 60seconds was trial and error over the course of several weeks a few winters ago. yet warming up that stove pipe does wonders for the draw. Top down is a good way to light yet take me a while to set up, so I don't do it. I uses this GAS/Propane bottle (they are about $20 from Home Despot)

Ray

 

[mellow]

I would replace the 90 with 45s before I went this far but there are products that can heat your liner: http://www.chimneylinerinc.com/specialty_parts.htm

 

[shawneyboy]

What do you mean by "top down"?

I am using very dry wood, starting with a little newspaper and very dry kindling, then slightly bigger, then slightly bigger.

Top down means just that. Bigest pieces on bottom, then in the middle, medium pieces, then on top kindling. It is counter-intuitive but it works. I have used a variant of it from time to time. It heats your flue before the wood really starts to outgas, which should mean less smoke spillage and hopefully better draft and easier startup.

See this thread... https://www.hearth.com/econtent/index.php/forums/viewthread/60484/

 

[gbailey1972]

Have been battling classic "cold chimney syndrome" with our new wood stove.
I've read a few suggestions, just wanted to bring it up again, and see if there were any fresh ideas out there?

Our setup–
Napoleon 1900, sits in basement.
Flue is single wall pipe, goes up about 2', takes a 90 degree elbow, runs about 2 feet to thimble.
I have a 1/4" rise per foot in the horizontal section.
Brick chimney is exterior, with new SS insulated flex liner.
Chimney extends height of 2 story house plus about 3 feet above the peak.

When starting I've tried the newspaper trick, but without a direct route to the flue, the smoke just pours out the front.
I tried sticking a Pelonis heater in the stove for 20 minutes prior to startup, didn't seem to make much difference.
Have tried doing this with a nearby window open, didn't make any difference.

My next attempt will be a propane torch to preheat the stove for a couple of minutes, or a piece of a fire-starter log.
I've also seen the suggestion to replace the 90 elbow with a 45/diagonal pipe/and second 45.

Any other suggestions?

A friend of mine has a setup that somewhat resembles yours. He installed a "DrawCollar", see this site, http://www.drawcollar.com/. He loves it. He has the timer on his, sets it for 15 minutes and then cranks up his kindling fire, top down. Hope that this may help.

 

[jeffs]

What do you mean by "top down"?

I am using very dry wood, starting with a little newspaper and very dry kindling, then slightly bigger, then slightly bigger.

Top down means just that. Bigest pieces on bottom, then in the middle, medium pieces, then on top kindling. It is counter-intuitive but it works. I have used a variant of it from time to time. It heats your flue before the wood really starts to outgas, which should mean less smoke spillage and hopefully better draft and easier startup.

See this thread... https://www.hearth.com/econtent/index.php/forums/viewthread/60484/

Okay. I'm not even putting big stuff in until I have a good pile of small kindling roaring.
It's the initial lighting I'm having the smoke issues with.

By the time I get to the big stuff the flue is fine.

 

[shawneyboy]

What do you mean by "top down"?

I am using very dry wood, starting with a little newspaper and very dry kindling, then slightly bigger, then slightly bigger.

Top down means just that. Bigest pieces on bottom, then in the middle, medium pieces, then on top kindling. It is counter-intuitive but it works. I have used a variant of it from time to time. It heats your flue before the wood really starts to outgas, which should mean less smoke spillage and hopefully better draft and easier startup.

See this thread... https://www.hearth.com/econtent/index.php/forums/viewthread/60484/

Okay. I'm not even putting big stuff in until I have a good pile of small kindling roaring.
It's the initial lighting I'm having the smoke issues with.

Try the top down, maybe it works, maybe it doesn't but heck it is worth a try. Set it up, light the knots, and immediately close the door. If it works great, if not, no big deal.

 

[PA Fire Bug]

I have the same problem depending on the weather and outside temperature. Opening a window or door did not seem to help but I do it anyway. I've burnt a few top down fires but not when the downdraft was so bad that I could feel cold air moving in the stove. If I notice a downdraft, I usually burn loose newspaper before I load any kindling. I've used pieces of cardboard without kindling as well. Regardless of what I've tried, smoke will leak out of the stove until the flue gets warm enough to reverse the downdraft. Candle wax or super cedars also helped. Loose newspaper has worked the best since crumbled newspaper stops burning and smokes. This past week was the first week that was cold enough to keep a continuous fire. Having a warm chimney and hot coals in the stove is really nice.

 

[bogydave]

I have the same problem on cold stove, cold days.
Even after the 90° to two 45°s, better but not a 100% cure.
I have an outside clean out "T", I can pull the plug & hold burning newspaper there to get a draft started.
I thought about trying a shop vac, & blow up the chimney to get the cold air out but never tried it after I did the outside newspaper in the "" trick.
The hair dryer or propane torch may work for you.
If you get a good fairly easy trick, let us know, lots here have the same issue.
Few times a year for me, when I start burning, usually 24/7. So never tried the other tricks.
Good luck.

 

[FPX Dude]

Hair Dryer +1

 

[jeffs]

Lots of good suggestions.


Will be trying...

a top-down fire (Never heard of this before, and being a long-time camper and Eagle Scout it sounds counter-intuitive, but am willing to experiment!)

hair dryer blowing into my outflow (which I now know is in front, not in the back... duh...)

another idea I had was a heat gun, (probably puts out more heat than a hair dryer)

super cedar starters, found a great deal on these at Amazon

Thanks all, keep the ideas coming, I'll report back after I've tried a few of these.

 

[DanCorcoran]

I think Super Cedars beneath dry kindling and small splits will do it...the SCs burn for 20-30 minutes.

 

[jeffs]

Where do you guys get your Super Cedars, (best price)?



I also saw these...

they get consistently good reviews, and the price looks very good.

http://www.amazon.com/Rutland-50B-P...sr_1_sc_1?ie=UTF8&qid=1323783081&sr=8-1-spell

 

[oldspark]

"another idea I had was a heat gun, (probably puts out more heat than a hair dryer)"
That's for sure I wonder if you could just lay it in the wood burner and run it for a few minutes (with the doodr closed lightly on the cord), maybe a little cube heater wood do the same thing.

 

[Battleaxe]

I have an exterior chimney with a hearth mounted stove and I packed Roxul around the insulated flexible liner at the top of the chimney just under the cap to help keep the heat down in the chimney. The cap, being metal, is heat conductive and even if well-sealed you'll lose some heat there if not insulated, especially when it's really cold outside. Even though the liner is insulated it still loses some heat along its length which rises to the top and packing Roxul around the liner to fill the gap between the liner and the chimney walls helps keep the heat down in the chimney. The more Roxul you can't get down in there the better. You could even use a broom handle to stuff it down in there, depending on how tight of a fit your liner is in there. Be careful not to damage your liner. If the chimney is cold then more insulation will help.

 

[firefighterjake]

Where do you guys get your Super Cedars, (best price)?



I also saw these...

they get consistently good reviews, and the price looks very good.

http://www.amazon.com/Rutland-50B-P...sr_1_sc_1?ie=UTF8&qid=1323783081&sr=8-1-spell

http://www.supercedar.com/

Thomas is a member here . . . if you contact him he may send you a couple free samples . . . but be forewarned . . . if you try them you might get hooked. They're also running a 10% off sale right now . . . I think.

 

[WarmInIowa]

+1 on the hair dryer and top down method. I understand what you are saying, the top down won't cure the problem - you need the hot air in the chimney before starting sometimes.

 

[WES999]

Try a propane torch, use a heavy duty one like a TS 8000. Direct the torch above the baffle, You can raise flue temp by about 20 °F in a minute of two. Then use the torch to light one or two fire starters. I use this method on my Fisher in the basement, it works for me.

 

[jeffs]

Well, I tried the heat gun last weekend. Set it on high (1000º) and aimed it up above the baffles for a good 5 minutes, then started with a Lightning Nugget fire-starter.

After a few minutes I thought I had success. The kindling was raging (I keep a big washtub full of very dry maple sticks nearby, and had a good-size pile of those raging in the stove). The flames were licking out top of the door opening, but not a lot of smoke. After a few minutes I started to slowly shut the door and the blaze lessened. Like a dummy I eventually shut the door all the way, thinking with the inferno I had going, and the pre-heating I had done with the heat gun, surely there must be enough draft now. Wrong. When I shut the door, the whole thing died (yes, I had the draft reg. all the way open). So now of course the stove is filling with smoke and it starts pouring out of every opening. Well, I'd been there before, so I opened the door, gave a good blow on the pile and WHOOF, it ignited again and stopped smoldering. A few minutes later, things finally warmed up enough to get the draft flowing the right. (After setting off the smoke alarms).

Lessons learned–

1. Flames licking out the front door mean the draft isn't going up the pipe yet.
2. Don't shut the door until the draft is definitely going up the pipe.

Question–

It seems like a lot of the heat (at start-up) is coming out the door, which means it's not going UP the pipe to warm the flue.
Seems like I need to keep the door closed partially to keep that heat in the stove, and UP the pipe?

I'm thinking maybe keep the door 80% closed from the get-go, that way the fire grows in proportion to the air it's born with, but I keep more heat inside and going UP.
Also thinking just run the heat gun a little longer?

 

[FPX Dude]

Wow, this still sounds wierd, I really don't like those "flames licking out the top of the door opening" either, that kinda scares me.

It's not so much the heating of the baffles but getting the air moving the other way as in UP the flue. Here's what I do:
Step 1. Open a window closest. Not just 8" but wide open, a full 2 ft. I know kinda weird to let in all this cold air but you gotta change the air flow direction asap.
Step 2. Now, I have a deflector plate at the back of my box, I would slide that out as it's removable (don't know if you have any such option? but mine just literally just sits on some tabs so just slides out).
Step 3. Make sure your bypass is open, then stick the hairdryer right up the flue, usually no more than say ~30 seconds, but you gotta get it directly up the flue.
Step 4. Then, put the deflector plate back in, AND then take a lighter and hold the flame up to the flue. If the flame is not sucking up the flue and out, I do NOT even attempt to light as the draft is not even ready and try again!