Quick help request - how to cool down overheating stove

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Slow1

Minister of Fire
Hearth Supporter
Nov 26, 2008
2,677
Eastern MA
I have too hot a load going - It seems too many envi blocks or just too much draft... anyway, bottom line is that my flue is steadily going up - now at top of "safe" zone - 575 on the therm. Surface temp is reporting 500. I'm getting lots of "puffs" in the stove with, some wanting to push the top load door up (one did). Advice anyone?

I know... risk of too much sawdust... ug. Any way to cool this baby down or do I need to sit here watching it all night? I tried reducing air intake, but that made the puffing much worse. Back of stove is starting to glow... eek!

9:47 update - stove top approaching 600, flue slightly down (just under 575). I have a small fan (best I could find) aimed at the back of the stove... trying to get it to go behind the heat shield where the glowing is.
 
A stove surface temp, or single wall surface temp of 500-575 isn't bad.

Ways to cut down the heat from a fire:

I'd cut down the air as much as possible.

The fan is a good idea.

I have set tubs of water on top of the stove to absorb heat from it. It's not fast, but it does pull the heat.

you said you had a top door? Baking soda or ash dropped into it? It smothers a grease fire.

Matt
 
9:55 - flue up to 600 (over redline) Glowing bright on back. Surface down a bit - 575. Thinking of blocking off the OAK intake... is this safe to do? Will it work... I'm really hoping someone is out there who can advise!
 
I'm more concerned about the flue temp going to 600 and rising along with the whole back of the stove being red at the moment... Thoughts? Am I in a panic for nothing?
 
Also - I do have the air reduced as far as it can go (I figure I may as well state that in case it was not assumed) I have no more factory controls available to reduce air supply... ug. I feel rather helpless other than to watch.. thus the consideration to cut the air intake at the OAK...
 
VC Everburns have a history of glowing. Not something you want to hear, but when you get a chance, you can do a search and read about it. If it makes you feel better VC says it's normal.

Matt
 
How about opening up the damper to bypass the everburn? It seems that is the area generating the excess heat... if I did that would it let things cool down or just add to the problem by letting too much air get to the load and heat it up even more?
 
Your flue is made of steel. It can take 600 degrees.

Cut your air. Let it cool and get some rest.

Matt
 
First do not panic. If your stove is overtiring it will cool down. Just keep a watch. You mentioned sawdust you are not using sawdust to feed your stove are you. Maybe I misunderstood but lots of sawdust in a wood stove is asking for trouble. As far as covering the oak some people do do this to help control runaway fires. In the future if you want to be safe and have strong draft install a damper. You will get much better control over fire.
 
I saw the title of the post and chuckled 'cause here I am eyeing my stove which the rutland is indicating 725 on the door right now. I start cutting back when it nears 800. Besides, at neg. 8 outside and 74 in here, I'm not complaining. Sounds to me like the concensus is that your running your stove within normal range. Enjoy the warmth!
 
I refer to Bio-Bricks and Envi-Blocks as "sawdust" - i.e. compressed sawdust vs 'real' cord wood.

I put a piece of foil over the OAK with holes punched in it to allow what I estimate to be about 40-50% of the surface area to be open. Over the last 5 mins since doing this, the flue temp has gone down from 600 to 575. Puffing has increased though - I just got one that was enough to blow the foil off (it is being held on by the draft pull and a bit of friction around the edges).

Looks like I may have a semi solution to slow this, but I will be babysitting... I appreciate the input - please keep it flowing as I'm still not quite comfortable with this situation.

The amount of Envi-Blocks I put in should be good to burn for about 6-7 hours.. I may be in for a long night here... ug.
 
brooktrout said:
I saw the title of the post and chuckled 'cause here I am eyeing my stove which the rutland is indicating 725 on the door right now. I start cutting back when it nears 800. Besides, at neg. 8 outside and 74 in here, I'm not complaining. Sounds to me like the concensus is that your running your stove within normal range. Enjoy the warmth!

I just wonder about the bright glow from the back and the constant increasing flue temp... there is a lot more fuel to burn and it was not leveling off (until I blocked OAK). Perhaps you are right and this is newbie jitters... I realize others have reported glowing backs on these stoves and there are reports that it is "normal" even according to VC even in contrast to their manual, but I guess I'm a control freak? I like to know that I can stop it when I need to? It seems that nothing happens really fast when it comes to stoves - i.e. you can't really quickly change the burn - adjust the air and wait to see what effect it has before assuming it is done, right? well... I don't want to see melting stove parts or a chimney fire kick off before I figure out how to start slowing this thing down! Ug... ok, I'm tired and it is late. Thanks to all for putting up with me.
 
Tomorrow head over to a Radio Shack. Buy a little 115V AC electric box fan. They are 3 to 4 inches square and move a surprising amount of air. They are made for cooling electronics so they can take a fair amount of heat. I have 2 sitting behind my stove to move a bit more air now. They can be stored anywhere since they are so small. Pick up a few. It'll ease your mind.

Matt
 
This thread scares me a little,

In my defiant encore model 2190 manual it tells me the range for "high heat output" is like 550-650 degrees and that sustained temps over 750 can cause damage. I try to keep my burn around 6-650 most of the time as measured on the griddle top, is this too hot? I've never seen any red anywhere and no sign of overfire, am I wrong in maintaining these temps? Also, I'd like to measure the flue temps, but I'm using double wall stovepipe from the stove to the class a chimney so I assume I won't get an accurate reading. Is the some sort of a probe thermo or something for a double wall pipe?
 
Phishhead - sorry to scare you... I'm still in a bit of a sweat and it isn't from the heat in the room.

Right now (11:28 my time) looking at a griddle temp of about 490 and flue at just under 550 (single wall surface mount measurement). I still have the foil with holes on the OAK and fan pointed at back of stove with air control all the way off. Less puffing going on, fire appears to be more stable, but I don't trust what would happen if that foil fell off and one good puff would likely drop it. Back of the stove is still glowing, but much less bright than before so I think things are cooling down. I REALLY wish that IR thermometer I ordered at end of Nov wasn't backordered from hell! I could get some interesting measurements off that glow I'm sure.

Ug.... I want to see flue fall back to my normal cruising temp of 400 before I go to bed... somehow I wonder if that will happen. I think this is probably an overdraft related issue. I also put this load into a hotter stove than I have ever done before with the bricks so they didn't have to warm the stove this time. Outside it is now 8*f which is unusually cold for us (coldest I've loaded like this)... too many variables changed to go trying this load at night I guess... should have done it on a Saturday daytime. Oh well, live and learn (as long as the 'live' part stays there eh?).
 
11pm here. Things are much calmer.. at least I am :-)

Stove top is a nice 550 (I don't mind it going up to 600+) and the flue is down to a very comfortable 450. Fire has occasional puffs of flame inside, but nothing that really seems to have any real "oomph" to it - i.e. the foil over the OAK has not fallen off in quite a while and I don't think the pot of water on top of the griddle is back to being just a humidifier rather than a weight to keep the griddle closed. The stove back is no longer glowing (at least if it is I can't tell so it doesn't matter now does it?).

So... hmm... so.. perhaps in a bit longer I'll head to bed and see what it looks like when I get up in the morning.

On the bright side, besides learning a few new things (will have to figure out what exactly of it is useful tomorrow), the house is a bit warmer than I had expected and the wife did not come down to see why I am still down here so she is calmly ignorant of this whole event (ahhh.. bliss).

Thanks to all who read and took time to reply. I bet tomorrow when I re-read this thread I'll be feeling a bit foolish, but oh well! at least the house isn't burning down and I'll walk away from this wiser in some way or another.
 
Although a bit exciting, from what you've reported it doesn't sound like there is too much here to get too worried about. The Encore can handle these temps. Many of us run our stoves at the edge of 700 degrees in cold weather. And this is why you have that expensive flue system installed. It's for peace of mind when things get hotter than anticipated.

These stoves do glow in back at times and I agree that is disconcerting. How many BioBricks were loaded into the stove? Were they started from scratch or placed on hot coals?

Sounds like you've learned some important lessons including to learn your wood (or biobricks in this case) before you need to push the stove. If possible, experiment with full loads and the limits of the stove on a Saturday morning when there's time to observe, adjust and learn.
 
EatenByLimestone said:
Tomorrow head over to a Radio Shack. Buy a little 115V AC electric box fan. They are 3 to 4 inches square and move a surprising amount of air. They are made for cooling electronics so they can take a fair amount of heat. I have 2 sitting behind my stove to move a bit more air now. They can be stored anywhere since they are so small. Pick up a few. It'll ease your mind.

Matt

I wonder if the optional blower kit for this stove would help reduce the glowing issue... I haven't looked to see where it directs the airflow, but if it did blow it over the back of the stove behind the head shield I wonder if that would help keep that cooler... ? I know, hijacking my own thread.

I am using fan that is about 8" square now - it is actually an electric heater that has a fan-only setting. It is the only fan I could dig up that is portable and I figure the plastic on it should be able to handle a little heat. Not sure that I want to leave it there unattended, but it's doing whatever it will do while I'm sitting here watching. At least I THINK it is doing some good... makes me feel better so I suppose that is some good.
 
BeGreen said:
Although a bit exciting, from what you've reported it doesn't sound like there is too much here to get too worried about. The Encore can handle these temps. Many of us run our stoves at the edge of 700 degrees in cold weather. And this is why you have that expensive flue system installed. It's for peace of mind when things get hotter than anticipated.

These stoves do glow in back at times and I agree that is disconcerting. How many BioBricks were loaded into the stove? Were they started from scratch or placed on hot coals?

Sounds like you've learned some important lessons including to learn your wood (or biobricks in this case) before you need to push the stove. If possible, experiment with full loads and the limits of the stove on a Saturday morning when there's time to observe, adjust and learn.

re: temps - I need to learn what is ok on the flue temp.. surface temp here never got anywhere where I would have worried (I've had it at 700 before, here it peaked at 600). It was the flue that caught my attention - the only reason I became seriously worried in the first place is that my thermometer has an "overfire" range that begins at 575 and I had only exceeded this once before. That time cutting air and engaging the everburn brought it down right away. In this case, everburn was cooking already and air was cut and temp was just going up up up...

re: glow - this is the first time I have seen it. If I didn't know it was bad I would have thought it was rather pretty really...

re: How many bricks? Actually I was using Envi-Blocks (larger and more dense than bio-bricks). I had 6 in there this time. I have had loads with 4 Envis and 12 BB's before with no problems at all. Thus I (obviously mistakenly) figured going with 6 Envis and 2 BB's (to get them going, BB's start quick, Envis are harder to light) would be safe. I did have a small bed of coals that I raked all to the front (I think that was mistake #2, I should have put the bricks in front, coals in back) so that I could stack bricks flat on floor of stove and pack them tight as possible.

re: experiment on Sat mornings - I could not agree more. Tomorrow is going to be one seriously long day for me, heh. At least this coldest night of the season I don't think we'll be waking up cold, heh. Then again, I won't wake up early to feed the fire so maybe that is a mistaken assumption too, I'll have to see in the AM.

11:40p - stove top now a nice 525, flue at 400. I hope it stays nice and stable like this for rest of burn - I imagine it will. I won't be changing anything at this point!
 
Glad this turned out ok - these are the times you want to make sure your chimney has just had a fresh sweeping ;-)

There is a larger issue here ....

I have been reading more about EPA stoves (as I am still trying to find the best solution to replace my old Cascade Triumph) and the inability to control them if they start to over-fire. I believe over firing is partially the result of creating stoves that have to meet strict emission standards - there is always some air allowed into the unit and the user has no complete OFF control. Kind of like driving a car with no brakes. The issue seems to have been well described and is loosely termed the "Florida Bungalow Syndrome".

At least with an old non-EPA stove, you can simply shut off ALL the air to the firebox and starve them into submission (this is the routine promoted to this day for a chimney fire by the way). Using a flue damper may help regain some more control, but it is still working from the wrong end in my opinion. I would like to find a new EPA stove that still provides a way to have maximum air control. So far on my hotlist, The Regency 3100 and PE Summit don't offer this control.

Any suggestions for EPA stoves that allow you to shut off air intakes fully, when it turns into a wild beast? A drop in outside temperature combined with an over drafting chimney and very dry wood, can make the most seasoned homeowner nervous fast. I think EPA stoves need more user defined air control or at least, a panic OFF control that shuts down all incoming air. In the event of a serious chimney fire, it seems an EPA stove, loaded with wood, is going to be a real nightmare.
 
I do not think your going to find an EPA stove that will allow you to shut down completely. If it did completely shut down then it could not pass an efficiency test. You say you do not like dampers but in fact they are the perfect way to keep a stove under control when strong draft is the problem. I am a new user of an EPA and still run 4 other none EPA stoves. I thought I knew everything about burning after 40 years burning but this new stove has taught me a thing or 2. If you get chimney fires then maybe you should not get a new stove as the EPA stoves can not take green wood like the old smoke dragons can. There is no getting around it if you go for a new EPA stove you need to pay attention to operating procedures [dry wood] much more closely than you would for the old stoves. All that being said I love the T6. It is doing a great job of heating but what I like most is its unbelievable ease of use. I never have smoke in the house and if there is a coal somewhere in the box it will start up easily. I also like how I can see whats going on.
 
Now I understand. I was wondering for a while why you couldn't just close off the airflow and put out the fire. We have an older stove and have done that on occasions. Seems crazy that new stoves have no way to cut off all the air and shut them down in emergencies.
 
glad to hear you like your T6.

Thanks for letting me know about new stoves fussyness for dry wood ... that is important info, but not always achievable for everyone, without some proper knowledge and planning. I have some 8 month Birch wood this year and it burns great in smaller chunks in my Triumph, but I'm guessing I'd be cursing a new stove on this wood.

For the record, I've never had a chimney fire and don't plan on it (I inspect and clean 2X per year - just cleaned today as matter of fact). I may have to settle on a draft control if my 30' chimney pulls too strong for a new EPA stove, but I still think that should be a secondary option of control. I mean really, can't they make an EPA stove that passes emissions and still allows users to stop incoming air completely when really needed? Of course they can, and should, at least as a safety measure. No air = no fire. No air = no wasted heat up the chimney when the stove is off. Not holding my breath for new Air/OFF features coming back to EPA stoves, but me thinks someone dropped the ball at the EPA on this issue and it seems I'm not alone.
,
http://www.gulland.ca/florida_bungalow_syndrome.htm
 
Well, I'm glad to say that my manual "air control" - covering the OAK inlet with foil (albeit allowing some air through) worked out great in the end. I ended up going to bed around midnight after the fire had been stable for an hour and no more puffing was going on, glowing gone etc. Amazing thing too - in the morning (6a) I had a very nice bed of coals. I have NEVER had that after an overnight burn. Glass was mostly clear (small dark area on one side where one of the bricks was a bit too close I think - once it expanded anyway). So, I think it was a fairly clean burn as well. Hmm... perhaps onto something here in terms of getting longer burns. Additional note regarding draft - not only was it a cold night, but the wind was up too - that may well have increased the draft (or at least made it inconsistent?).

So - now my project is to make a manually adjusted semi-permanent mount air inlet control for this stove that attaches to the OAK. I hope to use off the shelf components - not sure what yet, but I have neither a machine shop nor the skills to use in one so I have to assemble what I can find. In the meantime I'm playing with different foil covers to see what affect they have (checking for smoke output - so far I have not choked it back far enough to cause any... interesting).

Another note - I at least can have confidence that the lower part of my chimney got cleaned (burned) out that night eh?

Re the Florida Bungalow syndrome article - this is were I got the inspiration to put the control on the OAK instead of putting a flue damper in. Seems the author knows more about stoves than I do and that is his recommended solution, so here I go....
 
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