Puff Back With Wood Stove?

Post by **Lightning** » Mon. Feb. 03, 2014 2:11 pm

When is the last time the chimney was cleaned? It could be clogged up with creosote.

badlegdave · Post by **badlegdave** » Mon. Feb. 03, 2014 3:25 pm

Soul. I have a 35 year old Glacier Bay wood stove that is running presently and has almost continually since October. Blow backs as I call them are usual when the air intake is cut back to a minimum. The wood produces a lot of smoke and of course smoke is unburnt fuel. A blow back occurs when the stove gets a "breath of fresh air" from a down draft or just an area of wood in the stove that is just about ready to flash over. When it ignites it sometimes will ignite the rich smoke in the stove quickly enough to increase the pressure within the stove. The pressure exhausts mostly up the stack but it is not unusual for a volume to be exhausted out the air intake. Sure scared me when I was new to burning. I found the remedy is to open the air intake until I am able to hear the wood ignite and increase its draw on the air intake. This should not take too much. Let the fire increase the temperature of the chimney before lowering the intake. This should improve draft and lessen the occurance of blow back. Also, be sure that there is no obstruction in your chimney and have it cleaned on a regular basis expecially if you are running the stove for long intervals. I generally brush out my chimney once a month during the heavy usage months.
Depending on your ability to do it yourself, fiberglass screw together rods and a properly sized brush might run you $75.
Blow back does reck havoc with smoke detectors does it not?

freetown fred · Post by **freetown fred** » Mon. Feb. 03, 2014 3:32 pm

INDEED it does

D-frost · Post by **D-frost** » Mon. Feb. 03, 2014 3:43 pm

Soultinter,
Back in the day of wood burning, I had a stove in the garage with a metal chimney with a cap. The cap collects all the 'crap', trust me. My solution was put the cap on in April, and remove the cap in November. End of burn problems.
Good Luck

freetown fred · Post by **freetown fred** » Mon. Feb. 03, 2014 5:00 pm

df, with the wind I have on this hill of mine, I would of never thought of taking my cap off when I had the wood beast going, the house would of constantly been full of smoke. I also have one on my coal stove stack. I'm thinkin you meant--end of back puff problem in your post, not burn problem?

D-frost · Post by **D-frost** » Mon. Feb. 03, 2014 5:16 pm

Fred,
Yes, you are correct, end of back-puff. In my case, opening the feed door to a cloud of smoke that wasn't being drawn up the chimney. Every inspection of the cap showed creosote. That's burning oak, maple, and birch, all seasoned 1 year. The chimney was 14 ft. in the center of a 2 car unheated garage.
The cap kept out the rain and critters, but the stove vented better without the cap during the winter months.
Cheers

freetown fred · Post by **freetown fred** » Mon. Feb. 03, 2014 5:50 pm

I agree with ya Df, it's real hard to figure each individual house setting. I think the best we all do is sharing our actual experiences

I just need some answers from the OP to try & help him figure it all out.

VtFarmboy · Post by **VtFarmboy** » Mon. Feb. 03, 2014 6:06 pm

puffing is caused by the fact that it is easier for air to be sucked down the chimney than through the draft opening on your stove. It would usually happen when you first start your stove and the chimney/stove is cold. Try starting a smaller fire just a small amount of kindling and let the chimney warm up before you add wood for a larger fire. I have a soapstone stove and this is common. Cold chimneys do not draft as hard as a warm one. The other thing that could be happening is when it is windy out air can be forced down the chimney. the only thing you can do for this is to put a cap on the top of your chimney.

soultinter wrote:Has anyone ever had a puff back or violent explosion while burning wood? I have a hitzer 983 freestanding with double doors and spinner knobs, in addition to top sliders and the bottom ash pan slider that I don't use at all b cus I only burn wood not coal. But I have been experiencing some serious small explosions that scare the hell out of me and im worried the stove pipe is gonna blow off ! I know people get these with coal due to volatiles from the coal, but wood? and its not even after I stoke it, it seems slightly random. HELP!!!

buffalo bob · Post by **buffalo bob** » Mon. Feb. 03, 2014 7:02 pm

whenever I had puff backs with wood that was a good and urgent sign the flue and thimble and tin pipe needed a cleaning...we are in chimney fire season...check it out as a chim fire is terrifying ...

soultinter · Post by **soultinter** » Mon. Feb. 03, 2014 7:34 pm

The chimney is prolly 2 ft above peak. Not ideal but adequate. I do have black pipe from stove to chimney but stove is in basement and there isn't a lot of pipe. Plus I used 2 45's instead of 1 90. Ther is a MPD built in to the 983 and I usually keep it closed under most burn conditions. Closed being all the way in. But it doesn't cover the hole completely, by design. Took the cap off thinking it would help but no.

freetown fred · Post by **freetown fred** » Mon. Feb. 03, 2014 8:37 pm

OK--I'm hopin you got all your black pipe screwed together--3 if ya can--2 works--also screwed to stove??? 2-- 45's was good thinkin:)

Lu47Dan · Post by **Lu47Dan** » Mon. Feb. 03, 2014 8:53 pm

I get poofing when the stove has been running hard and the Bi-metal thermostat shuts it down. Then the wood gases accumulates and ignites when it gets a puff of air. I do not get them very often but they can be scarey.
Dan.

soultinter · Post by **soultinter** » Tue. Feb. 04, 2014 8:12 am

Well, it's definitely not a dirty chimney, I have never really had to clean my chimney during burn season but I did it yesterday and there really wasn't much accumulation. Maybe 3 or 4 large handfuls of creosote? And that's counting the accumulation at the bottom that falls out when I remove the undercap.
I'm starting to think its a problem with the house. The stove is in the basement of a large house and the whole second story is cathedral ceilings, which means only a thin layer of styrofoam insulation on the roof. I believe is called something like the " house chimney effect" ? Anyway, last puff back I witnessed I opened the window next to the stove and within a minute or 2 the flames were back on and everything was ok. I think that certain conditions "starve" it for combustion air.
But DANG is it scary!!!
The thing I'm really am scared of the most is that , I have 2 screws in every piece of pipe BUT, the hitzer has a a strange opening out of the stove, not a male extension but FEMALE, sooooo.... NO WAY TO SCREW IT IN. I used chimney cement around the opening and I'm sure that is the only reason it didn't blow off BUT.... It is now cracked up and falling apart, just redid half of it but I'm very worried.

Carbon12 · Post by **Carbon12** » Tue. Feb. 04, 2014 8:14 am

Where are you located?

soultinter · Post by **soultinter** » Tue. Feb. 04, 2014 9:08 am

Near buffalo ny