Lets talk Temps

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etiger2007

Minister of Fire
Feb 8, 2012
1,255
Clio Michigan
I have noticed that alot of fellow wood burners show off pics of their thermostst needles pointing to 600 to 800 degrees and above on their stove tops (freestanding and inserts). The magnet clearly states this is "Too Hot". Could some of you explain this? Are you not worried about setting your house on fire? When I have my small insert cranking the stove top gets to 300 at the highest and its obvioulsy not that hot, the fire inside the fire box is about 700 degrees. Thanks for any input and be safe!
 
Anything glowing red on the outside right because my baffle plate and tubes get red hot all thime just cant help it.
 
etiger2007 said:
I have noticed that alot of fellow wood burners show off pics of their thermostst needles pointing to 600 to 800 degrees and above on their stove tops (freestanding and inserts). The magnet clearly states this is "Too Hot". Could some of you explain this? Are you not worried about setting your house on fire? When I have my small insert cranking the stove top gets to 300 at the highest and its obvioulsy not that hot, the fire inside the fire box is about 700 degrees. Thanks for any input and be safe!


The magnet is a guideline. Not a hard and fast rule. Each manufacturer is a little different when it comes to 'too hot'. Hearthstone states that anything over 600 is too hot, Woodstock I think is somewhere around 700-750 (I think), some steel stoves put the number at 800-900, and some state that if the stove begins to glow red that the stove is too hot.

I am unfamiliar with your insert, and I know insert surface temps vary due to design and setup, but 300 degrees seems quite low. I'm not sure how you are measuring internal temps, but that too seems low as well.
 
Right. The magnetic thermometer is a guide. They sometimes can be way off. We had one once that was over 100 degrees off. A more exact measurement is an IR gun. Or you can also check your thermometer in your oven. Set the oven for 350 or 400 or something similar and set the thermometer in there. Do the temperatures match? Of course, if the oven is off then this would not work.

As for stove top temperatures, our particular stove says over 700 is overfire. Some say 600. Others take their stoves to 800. Follow what the manufacturer recommends and not what other folks do.
 
I measure my actual fire temp with a laser thermometer ( just point like a hand gun and shoot the laser into the firebox) and it is usually 100 degrees lower than what the magnetic temp gauge says i have on my door. I have a Dutch West wood insert from Vermont Castings and the fire box is small 1.3 cf the only temp the owners manual mentions is the burn temp to cure the paint and it says " the third burn should be between 500F and (260 to 370C) for 45 minutes. 370 c equals 698F however this is for paint cure can I go higher on normal burns?
 
In regards to your specific insert, DutchWest Model DW2500X02 insert the manual does not specifically state what is considered "too high" for this steel insert. But, it does state temps for the break-in fires. It states:

Each of the initial burns should be conducted as follows:
1. The first and second burns should be approximately 250° F (120° C) for approximately 20 minutes.
2. The third burn should be between 500° F (260 to 370° C) for at least 45 minutes. The important fact is the paint should be cured slowly. Avoid hot fires during
the curing process.


At the very least, this stove should be able to handle surface temps of 600 degrees.
 
Do you get enough heat with stovetop 300? How is your chimney - clean? Do you fill your stove up or do smaller fires?

Today we have 40 mph winds and I've a stove full of dry wood so I am watching it carefully and it got up to a bit over 650 where normally this mild winter the top has peaked out around 600. Fairly drafty antique house 2000 sf is warm in the stove room and 60s throughout the first floor. YMMV.

Mary
 
I think this is a somewhat funny story appropriate now. My buddy has my old Nashua in his shop. Ever since the day it was dropped off there the 2 draft knobs where turned full open and have never been touched since. He called the other day to tell me how good a job it was doing heating the shop. Stove top was 900 with fan on high! And thats where he runs it day in and day out. I guess their original ad about the dynamite was right. Don't try this at home.
 
You say when your insert is cranking the top is only at 300 degrees. That means either your definition of cranking isn't the same as mine or your insert has a very different design than my stove and your top stays at a low temperature even though the insert is heating the house. If your inside temperature is only at 700 then I tend to think you are not "cranking" according to my definition, which explains the low stove top temperature. If in fact the temperature inside your insert is only 700 degrees then I wonder if you are achieving any secondary burn at all. A fire that cool must be creating a lot of smoke and must mean you have a cool flue temperature, which together mean creosote accumulation. Thus it seems that by keeping the stove at a low temperature you are actually more at risk of burning your house down than you would be if you would burn hotter.

My stove top thermometer regularly reads 500 to 700 F with a nice fire going in the stove. A top temperature of only 300 means I get little heat from the stove relative to what I normally expect. Occasionally I see a temperature closer to 800 when I let the fire get a little hotter than I'd like. My stove is a small steel stove.
 
I get very good secondary burner ignition. other than refueling my chimney emits vapor. Im wondering if my heat is going up the chimney because even though I have a small fire box 1.3 cf my red oak and Black locust only give me good heat for about two hours, could it be that its only rated at 64% effiecent? My magnetic gauge on the door gets up to 650degrees. Keep in mind on my insert i have about an inch gap because the stove pulls cold air in from under the unit and blows it back out the top as hot air. My dealer was out and wants to rebuild my door new window gasket new door gasket and new door handle because Im not getting a good seal on my door gasket all along the top it is sealing on the other three sides. The main area this little guy heats is 1300 sf and it does heat it its about 72 in side with the gas furnace turned off and its 30 outside as of now.
 
I do burn small chuncks of wood about four inches in diamiter. Ive tried and tried to burn bigger logs but they tend to smolder and I can only fit in two because of the fire box being 1.3cf.
 
Just checked my fire box temp with the laser thermometer with the door open and it was over 900 degrees the laser only checks ups to 900 degrees so I should be over 1000 degrees temp in the fire box. Stove top still only 300 degrees. Wood reduced to a big pile of coals after an hour of burning hot.
 
I run constant temps of 600 and spike at 800 for about 15 minutes on the flue I do get worried when I pass 900 as it can run away real fast in the high temp range. Check your draft if it is consistently doing high temps and fast burns, our setup is high elevation and without a damper on this stove it burns very fast into coals though it will hold a coal bed forever. There is a device called a magnehelic gauge that I ended up using and discovered that we have a ton of draft! It should read .05 - .07 on the gauge we where drafting at .12 which is very high. Your problem sounds exactly the same as we where having. This is just a thought to try wood stoves can be quite finicky and it could be any number of things. Also if you have too much draft the heat will go straight out and super heat your chimney!

Pete
 
Well im not sure how much draft i have but i do know i have a good one one. When I crack the door you hear the swooshing of the chimney, what did you do to correct this problem of high draft?
 
etiger2007 said:
Well im not sure how much draft i have but i do know i have a good one one. When I crack the door you hear the swooshing of the chimney, what did you do to correct this problem of high draft?

I have a damper in the pipe to fix this issue however if you have an insert you will most likely have to use a draft reducing cap to accomplish the job. I do not know the technical name for this but someone will know and hopefully respond.

Pete
 
Well I stumbled on something today, I was sitting in my wifes library drinking coffee and I had my kindling going, as I sat there I was burning with the blower off, and I thought wow this thing really radiates the heat. Well all day i burned with the blower off and my house stayed a nice 72 degrees. My stove top temps exceeded 400 degrees for awhile today up to 450 to be exact. My wood last longer too, I would say now i can get five or six hours of heat out of this thing, thats the door themp gauge reading 400 degrees while it dies and 500 to 600 degrees for the first two and a half hours of burn. I have a fan on the mantle pushing the heat out of this room into the rest of the house. I think with my stove the door temps makes the most sesnse because my stove top has a good inch gap for the blower air to pass through. Im still getting a bigger stove 2.0 and bigger fire box and it had to stick out onto my hearth, if I can get that kind of burn with a 1.3 cf box 2.0 will be real nice. Long burns my friends.
 
etiger2007 said:
Well I stumbled on something today, I was sitting in my wifes library drinking coffee and I had my kindling going, as I sat there I was burning with the blower off, and I thought wow this thing really radiates the heat. Well all day i burned with the blower off and my house stayed a nice 72 degrees. My stove top temps exceeded 400 degrees for awhile today up to 450 to be exact. My wood last longer too, I would say now i can get five or six hours of heat out of this thing, thats the door themp gauge reading 400 degrees while it dies and 500 to 600 degrees for the first two and a half hours of burn. I have a fan on the mantle pushing the heat out of this room into the rest of the house. I think with my stove the door temps makes the most sesnse because my stove top has a good inch gap for the blower air to pass through. Im still getting a bigger stove 2.0 and bigger fire box and it had to stick out onto my hearth, if I can get that kind of burn with a 1.3 cf box 2.0 will be real nice. Long burns my friends.

My stove has a 1.3 cf firebox. I never run the blower except when I get it a little to hot and want to cool it down. Plus its to noisy. I push my little stove pretty hard and stopped worrying about efficient burning long ago. Do I strive for long efficient burns?.....Yes but when its not cranking out the heat I want I add more wood or open up the air and let her eat. I guess where I'm going with this post is, try using your stove for a while with the blower and see what your results are. My stove top averages about 550-600 and when I'm really getting things up to temp it will be over 700 for an hour or so.
 
I have never not used my blower, today was the first day I turned it off and tried it. My stove top temps with the blower on high would be abot 300 the door temp 600. I think the blower eats my wood up. i have been burning with the blower on high for about 7 months of heating season three months last year and four months this year. I bought it mid Jan last year.
 
Where did two of my posts go in this thread?

One was asking about running the fan on a lower setting and the other commented on the 2.3 cu ft stove.
 
Its on another post "Trying to figure this out" Lets talk temps started out about people running thier stoves hot and got alittle off track lol
 
etiger2007 said:
Not sure i did read them and answered them?

Not sure. One asked if you could run the fan at a lower setting and the other commented on how the 2.3 cu ft stove will easily heat your house, give you longer burn times and increase your flexibility during colder temps.
 
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