why did my stove burp and is it safe

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gazelle

Member
Dec 4, 2009
18
SW VA
I have a new VC NC Defiant, tonight is the first time that I have been able to get it up to temperature.


So I have closed the damper and in the last hour the stoves flame has been going and then all of a sudden a blue flam gores from the top of the stove to the bottom like a flash and a bit of smoke leaks out the door. It basically appears to me kike gas is accumulating and it all of a sudden ignites. Should this happen? If so I am guessing smoke should not come out of my doors. The smoke does not come out of one spat but all around both doors, so this tells me there is a sudden build up of pressure.


Can I go to sleep tonight or do I need to shut it down?


Thanks
 
It sounds like it's losing draft. Can you describe the flue that is connected to the stove in detail? Also, what is the temp outside?
 
Wood is outgassing, gas is building up then igniting, and BAM!!! a micro explosion. pushes smoke outa every hole available. giver a little more air to sustain the burn and equalize the burn. then settle in for a night on the couch cause even me tellin you it"ll be fine wont settle your nerves any.
 
Don't cut the air back so quickly while it's outgassing. Hopefully that should fix the problem.

This is from the Encore NC manual:

"“Back-puffing” results when the fire produces volatile
gases faster than the chimney draft pulls them out of
the firebox. The gases back up in the firebox until they
are dense enough and hot enough to ignite. If your
stove back-puffs, you should open the damper to direct
more heat up the chimney to allow the smoke to rise
to the flue more quickly, let more air into the firebox.
Smaller loads of wood, larger pieces of wood and
avoiding overly dry wood loaded into a very hot stove
may help this problem. If back-puffing persists, contact
your dealer or qualified chimney sweep to help diagnose
the problem."
 
It is about 35-40 degrees outside right now and dropping



To show my newby ignorance what is the flue on these? Would that be the oxygen control lever? To me the flue is a pivoting flap in the pipe used to close down on older stoves.

This stove has a damper that is closed and the oxygen control is about 1/4 open

It then goes out a horizontal pipe about 2 ft then hits a 90 and goes up 22 ft through and 8 inch flexible liner that has insulation on the top 12-13 ft.


thanks for helping out a new guy folks. I appreciate it a lot.
 
and
avoiding overly dry wood loaded into a very hot stove


This may be my problem, I am burning a batch of store bought kiln dried wood to see if I can get my stove up to temp. I was having a problem before and thanks to great advice here am trying the store wood to see if my temp problem was a stove problem or a wood problem.
 
This was a chronic problem with my old VC Encore cat. We lived with backpuffing for 23 years. Some days it was impossible to run the stove with the cat bypass closed. No matter how gradually we turned it down, it would get unstable, leaving us with three choices. 1. Let it puff. 2. Feed it more air to keep flame going in the firebox and let the stovetop go past 800 degrees. 3. Run it with the bypass open but the primary air fully closed.

None of these options was very satisfactory to say the least. I was absolutely astounded when we switched stoves this past spring, and have had zero control problems. We're kicking ourselves for not tossing the VC 10-15 years sooner.

Good luck with your stove. I hope you can find a way to make it behave itself.
 
gazelle said:
It is about 35-40 degrees outside right now and dropping



To show my newby ignorance what is the flue on these? Would that be the oxygen control lever? To me the flue is a pivoting flap in the pipe used to close down on older stoves.

This stove has a damper that is closed and the oxygen control is about 1/4 open

It then goes out a horizontal pipe about 2 ft then hits a 90 and goes up 22 ft through and 8 inch flexible liner that has insulation on the top 12-13 ft.


thanks for helping out a new guy folks. I appreciate it a lot.

One thing to check would be to make sure that the 2' horiz. pipe is heading uphill towards the 90. Put a level on it and check. It should be pitched upward at least 1/4" per ft.
 
gazelle said:
It is about 35-40 degrees outside right now and dropping



To show my newby ignorance what is the flue on these? Would that be the oxygen control lever? To me the flue is a pivoting flap in the pipe used to close down on older stoves.

This stove has a damper that is closed and the oxygen control is about 1/4 open

It then goes out a horizontal pipe about 2 ft then hits a 90 and goes up 22 ft through and 8 inch flexible liner that has insulation on the top 12-13 ft.


thanks for helping out a new guy folks. I appreciate it a lot.

Gazelle,
Yea, you do need some help: A flue is a duct, pipe, or chimney for conveying exhaust gases from a fireplace, furnace, water heater, boiler, or generator to the outdoors.

The pivoting flap on the exhaust side of a stove is a "damper," and is typically used with older non-airtight stoves to control the air feeding the fire. The new stoves are air tight and so they control the combustion air using a draft control on the intake side of the stove. You can think of this draft control more as a draft compensator, that is, it's used to compensate for increased draft when the stove is hot, and decreased draft when the stove is cold.

Under most conditions, you won't need a damper if your stove is one of the new EPA stoves. If you have an older non EPA stove, then you may need the damper.

Keep reading!
Dan
 
have had that happen with my stove on a 15' chimney running straight up, burning seasoned cord wood, oak & hickory mostly. Solved the problem by making sure my chimney was up to temp before shutting the air control down. Basically was shutting the air down for a low fire before getting the stove fully up to speed. The stove i had before never had that issue, but after switching stoves i needed to adjust the way i burned slightly. The chimney isn't pulling the exhaust (gasses) out of the stove fast enough, they ignite (delayed ignition) and poof!! The hotter the chimney is the more draft or pull you will have.
 
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