Chimney Draft Failure

Chimney Draft Failure

PostBy: Lightning On: Mon Dec 17, 2012 10:46 pm

This morning I knew it was gonna be warm and I sent the wife a text saying we will be under a "low draft watch" today.. Knowing she didn't have work I didn't prepare the furnace for a low draft condition. Well she went out shopping for a few hours and when she came home she sent me a message saying that the low temp alarm (set for 130) for the flue pipe was beeping (on my handy remote BBQ thermometer ;) ). I immediately told her to go into the basement and look at the mano and sure enough, it was below 0 and the basement reeked of sulfur. SO, I had her hit the override switch for the draft inducer and took it up to a .03" WC. So no harm, no foul :D

My normal procedure for a warm day trying to idle the fire back is too -
1. Cut primary air to a sliver to keep a low and slow fire..
2. Open the MPD. (I usually leave it open unless its really cold and the baro can't keep my draft down to a .03"WC)
3. Open my secondary (over the fire air valve) to 50 - 100% depending on conditions outside.

*I've found that when I cut the primary air and give it more secondary it maintains draft. The secondary air doesn't aid much with combustion when running a low fire, but instead is just more heated air mass that goes up the chimney and keeps the draft. I've also added vents on two sides of the basement. These vents compensate for any (if any) stack effect going on in the basement from warm air going up thru the floor. The vents more or less keep atmospheric pressure between outside and the basement balanced since any negative pressure in the basement would cannablize draft pressure.

I'd like to hear what my other fellow coal burners do to keep a chimney draft under warm day outside conditions :D
Last edited by Lightning on Mon Dec 17, 2012 11:15 pm, edited 1 time in total.
Lightning
 
Hand Fed Coal Furnace: Clayton 1537G
Coal Size/Type: Nut Size / White Ash

Re: Chimney Draft Failure

PostBy: tcalo On: Mon Dec 17, 2012 10:57 pm

I find by opening the MPD 100% and bumping open the primary air a bit helps maintain a good draft. I never tried to crack the secondary air. Luckily I have an excellent draft and have run the MPD closed on mild, damp days without a problem.
tcalo
 
Hand Fed Coal Stove: Chubby Coal Stove
Coal Size/Type: Nut Anthracite

Re: Chimney Draft Failure

PostBy: jschaefer7406 On: Tue Dec 18, 2012 7:15 am

tcalo wrote:Luckily I have an excellent draft and have run the MPD closed on mild, damp days without a problem.


I'm fortunate to have this also. Chimney is in the center of the house and is good and tall ;).

I probably COULD leave the MPD closed on damp, warm days, but I try to leave it open if I know it will be warm and humid. The temperature doesn't scare me as much as the humidity or rain. Have heard that it reduces draft, not sure by how much. Need to get that manometer permanently plumbed in...

Haven't tried opening the secondary air on warm days either, too scared to rob primary air I guess :). May try it some day if I know I'll be up, usually sleeping during the day (working 12 hr nights :().

Joe
jschaefer7406
 
Stove/Furnace Make: Kogen
Stove/Furnace Model: Keystoner

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Re: Chimney Draft Failure

PostBy: Lightning On: Tue Dec 18, 2012 8:01 am

Nice! You guys are fortunate to have good drafting chimneys :) Mine drafts good too, until it warms up outside. Since it runs along the side of the house and was built with solid blocks, I'm guessing it takes a long time to adjust to ambient temperatures outside. When there is a sudden rise in temperature outside, the air becomes warmer than the chimney. This is when my draft fails unless I keep the secondary air open to keep warm air going up the chimney. I discovered this last year while I was using a 26 foot high stove pipe for a chimney hahaha... When the Sun would hit it, it would draft crazy, then as soon as the Sun dipped under the hill, draft would cut way back.
Lightning
 
Hand Fed Coal Furnace: Clayton 1537G
Coal Size/Type: Nut Size / White Ash

Re: Chimney Draft Failure

PostBy: I'm On Fire On: Tue Dec 18, 2012 12:43 pm

I've got a low drafting chimney but I never turn my draft inducer off. It runs 24/7 the entire season.
I'm On Fire
 
Hand Fed Coal Stove: DS Machines DS-1600 Hot Air Circulator

Re: Chimney Draft Failure

PostBy: michaelanthony On: Tue Dec 18, 2012 2:54 pm

Lightning wrote:
I'd like to hear what my other fellow coal burners do to keep a chimney draft under warm day outside conditions :D

...I will refrain from using the dryer, crack window abit more than normal ( I allways have fresh air coming in the basement when stove is running ), adjust weight on baro. so I have .04-.06 draft and open primary air to stove alttle, I would rather have a little heat go up the chimney than clean out stove and relite.
michaelanthony
 
Hand Fed Coal Stove: Vigilant 2310, gold marc box, vogelzang pot belly coat rack
Coal Size/Type: Pea, and a little nut
Other Heating: Very cold FHA oil furnace

Re: Chimney Draft Failure

PostBy: Boots On: Tue Dec 18, 2012 5:27 pm

Wow, i guess my draft is not as bad as i thought. On warm days when the boiler stays in low fire for extended periods i will drop down to slightly less than .01" wc. but if and when it go' s into high fire it will be back up to .03" wc. When it gets cold outside and the old girl idles for a while i will see .01"wc but i will get as high as .04"wc during high fire. I have not seen much higher than .04"wc unless it is windy out.
Boots
 
Stoker Coal Boiler: Keystoker KA-6
Hand Fed Coal Boiler: Burnham SFB 101 (sold)

Re: Chimney Draft Failure

PostBy: Lightning On: Tue Dec 18, 2012 7:12 pm

michaelanthony wrote:...I will refrain from using the dryer,

True enough! Anything sucking air out such as a dryer will create low pressure around it, provided the space is tight (no way for make up air to get in). I notice this too if a window is opened on the first floor - better have the basements vents open!!

Hey Boots, is that a hand fed boiler? I might have to have one down the road at some point to use year round :D
Lightning
 
Hand Fed Coal Furnace: Clayton 1537G
Coal Size/Type: Nut Size / White Ash

Re: Chimney Draft Failure

PostBy: Boots On: Wed Dec 19, 2012 4:55 am

Lightning wrote:
Hey Boots, is that a hand fed boiler? I might have to have one down the road at some point to use year round :D


Sure is, and I love her! Keeps the house nice and tosty and provides me with domestic too!
Boots
 
Stoker Coal Boiler: Keystoker KA-6
Hand Fed Coal Boiler: Burnham SFB 101 (sold)

Re: Chimney Draft Failure

PostBy: perch On: Fri Mar 22, 2013 1:19 am

i just bought my house i have no idea about the damper on the flue do i leave it wide open or cut it back its an old hand fired simplex multitherm it burns great the flue is almost wide open i just think alot of my heat is going up the chimney it burns real fast?
perch
 
Stove/Furnace Make: simplex multitherm
Stove/Furnace Model: not sure

Re: Chimney Draft Failure

PostBy: Lightning On: Fri Mar 22, 2013 3:34 am

perch wrote:i just bought my house i have no idea about the damper on the flue do i leave it wide open or cut it back its an old hand fired simplex multitherm it burns great the flue is almost wide open i just think alot of my heat is going up the chimney it burns real fast?


Hi perch, welcome to the forum :D .... I would advise you to start a new thread topic to draw more attention to get your questions answered. There are plenty of friendly people here willing to share their experience to help you 8-) ... I assume you are burning coal? More information is needed before advising what to do with your manual pipe damper. The more information we can get about your set up, the better we can offer advise..
Lightning
 
Hand Fed Coal Furnace: Clayton 1537G
Coal Size/Type: Nut Size / White Ash

Re: Chimney Draft Failure

PostBy: freetown fred On: Fri Mar 22, 2013 7:09 am

perch, also---post some pix of your stove set up--you know---pix worth a thousand words
freetown fred
 
Hand Fed Coal Stove: HITZER 50-93
Coal Size/Type: BLASCHAK Nut/Stove mix

Re: Chimney Draft Failure

PostBy: jpete On: Fri Mar 22, 2013 1:53 pm

My chimney drafts like a pile of mud so toward the end of the season, I have to foil over the baro to make sure ALL the air goes the way it should.
jpete
 
Hand Fed Coal Stove: Harman Mk II
Coal Size/Type: Stove, Nut, Pea
Other Heating: Dino juice

Re: Chimney Draft Failure

PostBy: Lightning On: Fri Mar 22, 2013 2:15 pm

jpete wrote:My chimney drafts like a pile of mud so toward the end of the season, I have to foil over the baro to make sure ALL the air goes the way it should.


On warmer days try running more secondary (over the fire) air. I've been able to maintain a draft even when it's approaching 60 degrees outside by doing that.
Lightning
 
Hand Fed Coal Furnace: Clayton 1537G
Coal Size/Type: Nut Size / White Ash

Re: Chimney Draft Failure

PostBy: whistlenut On: Fri Mar 22, 2013 2:36 pm

Please don't be afraid to install a draft inducer if your draft is marginal. The 'dirt nap' takes no prisoners, and I for one sure don't want anything to happen to you or your family.....or pets. More installs involve having to install an inducer, and really it is not too far from what oil, propane and NG units do with the pre-purge and post-purge set-ups. Many new homes and businesses are WAAAAAAAAY to tight for proper combustion, and if you go by the Fields literature, one square foot per every 100,000 btu's of output. How many have a hole a foot square, anyway? Boiler rooms need to be isolated if the inspectors get that particular. Ever been in a boiler room that was 33 degrees? More like 133 degrees.

Field Controls 46075300 Draft Inducer for 5-8 Inch pipe......
http://www.grainger.com/product/TJERNLU ... 01238694-2

Obviously there are many other devices, however I can't tell you to make you own for less......but search for 'draft inducers' and let your mind wander, if you choose!

Yes, you can use the chimney top variety, and don't laugh at the turbine models you have seen on attics or chimney tops......no power requirements, and they work very well. NO, Larry, no questions answered!!!!
whistlenut
 
Stoker Coal Boiler: AA130's,260's, AHS130&260's,EFM900,GJ&VanWert
Hand Fed Coal Boiler: Franks Boiler,Itasca415,NYer130,Van Wert
Hot Air Coal Stoker Furnace: Yellow Flame
Hot Air Coal Stoker Stove: Alaska-4,Keystoker-2,
Hand Fed Coal Stove: Alaska,Gibraltor,Keystone,Vc Vigilant 2
Hand Fed Coal Furnace: Van Wert, NYer's, Ford,Jensen.
Coal Size/Type: Rice,Buck,Pea,Nut&Stove
Other Heating: Oil HWBB

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