Advertised max burn times? Likelihood of achieving it?

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Mitch,
The stovepipe damper worked out great. I now have exactly the control I wanted. Even with the damper vertical, the stove is way less apt to runaway.

I still occassionally forget to open the damper before I open the door. The smoke alarm reminds me in about 5 seconds. There is no visible smoke but I have the ionization type detectors vs the photocell type.

MnDave

I have not used my pipe damper yet but like you said even with it open it adds more control.
 
Next time, try a load where you finally cut the air down one further notch, to the point where the secondaries just start to get flakey. That seems to be the sweet spot for our stove.
 
Burn time is a marketing term. It can mean what the seller wants it to.

I totally agree. I wish that I knew that when I was studying Quadra Fires literature.

So a stove that has a 16 hr burn time could very likely have a 12 hr period of meaningful heat.

I am confused. Are you saying that the stove is burning for 4 hours without producing meaningful heat? Maybe I do not understand what you mean by "meaningful heat".

MnDave
 
Next time, try a load where you finally cut the air down one further notch, to the point where the secondaries just start to get flakey. That seems to be the sweet spot for our stove.

I will try that. It could be that some combination of damper and burn rate setting is optimum. For this stove, it seems like the signal that the secondary burn has become flakey is when the stovepipe temp drops below 300F. Once it tips below 300F it just keeps dropping.

Sofar I have kept the damper at 45 degrees. At that damper setting the lowest burn rate that keeps the stovepipe temp at 300F is right in the middle of the control range on bar 3 (there are 5 bars).

I plan to find the damper setting that allows me to close the burn rate all the way and maintain the 300F stovepipe.

I realize that this experiment is very dependent on the quality of the wood. My wood quality is all over the place at the moment. That will change in the next 2 to 3 years. That is very exciting for me. I have a developing plan for my wood processing and storage area.

MnDave
 
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I totally agree. I wish that I knew that when I was studying Quadra Fires literature.

I am confused. Are you saying that the stove is burning for 4 hours without producing meaningful heat? Maybe I do not understand what you mean by "meaningful heat".

MnDave

It takes a while for a stove to get warm. Meaningful heat means to me that the room temps are not going down appreciably. Right now that could mean a 150F stove in our 40F temps, but in very cold weather that could mean a 300F stove. With the right wood a 12 hr period of meaningful heat is possible if we consider this from warm up to 150 or 200F to coal die down back at 150 or 200::F .
 
I have a enviro kodiak 1700 that has a 2.5 box and according to enviro is 84.7% effiecient. They advertise 8-12 hr burn times, ive been achieving 8 pretty regularly now that im filling the box as we are getting colder. I live upstate ny, not super cold but highs in the low 30s and lows in the mid 20s. In fact i loaded it up this morning at 8, went snowmobiling all day, went out to dinner after and just got home about ago thermo read low 200's and i had plenty of coals for an easy restart. thats nearly 13 hrs. house was 67 this morning, 70 when i got home. I have a raised ranch, 1300 sq ft main floor, and about 600 sqft downstairs thats finished with the stove downstairs. pretty impressed by this stove, as a first time woodburner myself. I grew up with a wood stove as a kid.
 
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With really dry wood, I've been able to get 8-10 hour burns with my Shelburne. Only with really dry wood, but why would anyone expect long burns with anything else?

I define the end of "burn time" as being when I can stick my bare hand into the coals and not get burned. If I get burned, it's still burn time.
 
BeGreen, if you are talking 150-200 degrees at the end, then my burn time just went to 10 hours.
 
BeGreen, if you are talking 150-200 degrees at the end, then my burn time just went to 10 hours.

The manufacturers are probably using a burn time that is talking about a stovetop a degree over room temp. Before I went to buy my stove, I was well-aware that
burn times are exaggerated. It doesn't bother me as long as the stove heats my home. It's 8 degrees, and I'm running 3 loads per 24 hours and keeping 2000+ square feet very comfortable. Last night, I filled the stove about 2/3 full at 10 p.m. This morning, I had time to open presents and make coffee before an easy restart at 8 a.m.
 
Last night was a cold one, 0F. I started at around 1 AM, the house was 70F. I let the coals die down. I pulled them to the front of the box. I loaded 2 splits E/W at the back of the stove. Then I put 7 in N/S. This filled the box to within 4 inches of the glass.

This was all the same wood which I believe is a hard wood due to its weight but it doesn't seem like red or white oak. This is my best quality and driest wood at 1.5 years c/s/s. I stuck around and watched the burn proceed.

Amazingly I was able to set the burn control on minimum and set the damper horizontal and the stovepipe temp held constant at 325F. The secondary burn was very stable.

At 9 AM it was 66F in the house and 7 F outside. I went down to check what I had for coals. I walked toward the stove with a big smile and two thumbs up. The stovepipe temp was 200F and I not only had a big mass of glowing coals in the middle of the box but those E/W splits were still intact!

Those coals could have gone another hour at least so I am going to say that was a 9 hr burn at 0F in an 1800 sf home with lots of windows!

I credit the drier wood for letting me turn the air down that much.

I was surprised that the 2 E/W splits were intact. They were covered with coals. I pulled back the coals and found them charred black. When I pulled them away from the back of the stove they did not fall apart. They were totally outgassed and not glowing. That is the first time I have ever seen that.

I plan to burn a totally E/W load of this same wood tonight.

One question I still have on the Quadra Fire 5700 advertised max burn time (15-21 hrs) is, "How do they run the stove that low?". It must be a trick they do with a few big blocks of kiln dried wood. I plan to call them and see what kind of answer they come up with.

MnDave
 
The manufacturers are probably using a burn time that is talking about a stovetop a degree over room temp. Before I went to buy my stove, I was well-aware that
burn times are exaggerated. It doesn't bother me as long as the stove heats my home. It's 8 degrees, and I'm running 3 loads per 24 hours and keeping 2000+ square feet very comfortable. Last night, I filled the stove about 2/3 full at 10 p.m. This morning, I had time to open presents and make coffee before an easy restart at 8 a.m.

Sounds like you are doing very well. 10 hrs on a 2/3 rds load.
What type of wood? Age and size splits? How many? E/W loading I presume.

Age of house? Average number of average sized windows?

MnDave
 
Ran 10 hrs today on a 2/3ds full load of doug fir and some alder, loaded N/S. This was the first load of the day. The stove top was 250 and the living room was at 74F when I reloaded with a few new splits. Had this been locust or other good hardwood and a full load I'm guessing it would have easily passed the 12 hr mark with the same results.
 
BeGreen, if you are talking 150-200 degrees at the end, then my burn time just went to 10 hours.

If it's cold where you are and you are pushing the stove harder than I (39F outside) then your burn time may be shorter. One thing I may be doing differently is that am shutting the air down sooner this year. The stove is running about 100F cooler at 500-550F, but it is cruising fine on softwood, which is a bit of a challenge at times. The reload was E/W, but just a few splits. With the oven going for Christmas dinner the house was plenty warm.
 
Sounds like you are doing very well. 10 hrs on a 2/3 rds load.
What type of wood? Age and size splits? How many? E/W loading I presume.

Age of house? Average number of average sized windows?

MnDave

I'm running a mixture of oak and small rounds of elm at the moment. All of my wood is seasoned for at least three years. That's overkill except for the big
splits of oak and hickory. The house is 20 years old but well insulated for its age, built into a hill, has 18 windows, and a big sliding glass door. A number
of the windows on the non-hill side are nearly floor to ceiling. We get some help with the passive sun during the day and have heavy shades for the windows at night.

I agree with BeGreen that cooking is a nice heating assist. With all of the cooking going on yesterday, I only went with two loads. Coals were pretty sparse after 14 hours, so I needed 3 sheets of newspaper on top to help get things going. Because there were still some small coals and lots of glowing embers, I would wager that Quad would have been keeping that burn time clock ticking.
 
I'm running a mixture of oak and small rounds of elm at the moment. All of my wood is seasoned for at least three years.
I'm jealous but on my way there.

Coals were pretty sparse after 14 hours,
I can't imagine a 14 hour burn with mine. I believe that I will get 10 consistently and maybe 12 hrs occassionally.

What is your draft like? Chimney length? Straight up? Stovepipe damper?

MnDave
 
I would wager that Quad would have been keeping that burn time clock ticking.

Missed that first time around. :)

Yes. How about Quadra Fire's advertised burn times. I am going to talk with my salesman today. I am going to request to speak with a company rep.

I plan to smile alot. At least at first. Maybe they will throw me a bone.

MnDave
 
I can't imagine a 14 hour burn with mine. I believe that I will get 10 consistently and maybe 12 hrs occassionally.

What is your draft like? Chimney length? Straight up? Stovepipe damper?

MnDave

I have 23 feet of chimney, but also two sets of 45/45 turns (taking it through the wall and then straight up)..

My draft is just okay during fall and spring. When it gets cold, like it is now for you and me, I have good draft. No stovepipe damper. I used to have one in my previous house, but found that it wasn't necessary. If you have a very strong draft, it's nice to have.

Good luck with Quad and let us know what they say.
 
Missed that first time around. :)

Yes. How about Quadra Fire's advertised burn times. I am going to talk with my salesman today. I am going to request to speak with a company rep.

I plan to smile alot. At least at first. Maybe they will throw me a bone.

MnDave

I think that Quad is talking about the time from the start of the fire until die down with some hot coals for the restart. With proper loading and turning down of the stove, In that case I would expect 14-16 hrs to be possible with the 5700, but haven't actually tried it. I do know I can do this with the T6.
 
With really dry wood, I've been able to get 8-10 hour burns with my Shelburne. Only with really dry wood, but why would anyone expect long burns with anything else?

I define the end of "burn time" as being when I can stick my bare hand into the coals and not get burned. If I get burned, it's still burn time.
Than technically, I can get 72 hours on my King any day of the week using your test.
 
I have 23 feet of chimney, but also two sets of 45/45 turns (taking it through the wall and then straight up)..

My draft is just okay during fall and spring. When it gets cold, like it is now for you and me, I have good draft. No stovepipe damper. I used to have one in my previous house, but found that it wasn't necessary. If you have a very strong draft, it's nice to have.

Good luck with Quad and let us know what they say.

You and I have the same chimney and stovepipe parameters. I have the same comments on my draft.

I wanted the damper so that I could get the longest burn possible which, if done right, is probably the most efficient burn. I can control the air to the point where my stovepipe temps locks at 300-325F.

I talked with my QF salesman. With the latest brochure in hand I asked him about the QF 5700 advertised max burn time (on low) of 15-21 hrs. Without hesitating he said that those are "factory conditions". He said that they use some special wood for that.

I told him that if the special wood is not readily avalable then the numbers are "not real world". I told him that I doubt anyone can get even 15 hrs on a 5700 let alone another 6 on top of that.

I went on to explain how I believe that QF's has exagerated their burn times and that this could hurt their sales on repeat business. I personally feel misled and wish that I had found this forum before I bought my QF. I like the stove but I feel misled by Quadra Fire. He said that he will take my comments up with his QF contact.

I invited him to read this forum. I think that he will.

Also, if you recall, I told him a while back that I put a damper in. He said that QF doesn't think they are needed. I think that I needed one or my burn times would be even less. He discussed my damper with the shop owner. The owner thinks that my OAK might be super-charging (my words) the draft. I doubt that because I blocked the OAK and it had little effect on the burn. My lower level has a 6" make-up air duct to the floor in the utility room 10 feet away... that's been code for a long time.

I wonder how many times a salesman visits a customer and observes the product in operation? My guess is not often, otherwise they could rattle off existing installs and how they perform. Also, this kind of information can be found right here on this forum. Any salesmen out there? I should make this the title of a thread.

Most people do not get into the nitty-gritty of fine-tuning their stoves. I do, and it will pay off in fewer trips to the woodshed, fewr chain sharpenings, fewer gallons of gas in the splitter...

MnDave
 
Than technically, I can get 72 hours on my King any day of the week using your test.
ohlongarm,
Your stove is in a class above most here. There is simply no comparison with a typical 3 cf stove.
MnDave
 
In that case I would expect 14-16 hrs to be possible with the 5700, but haven't actually tried it. I do know I can do this with the T6.

That gives me hope and motivation.

All this is making me rethink my comments in several old posts about fan usage affecting the burn rate.

I know that combustion engines are more fuel efficient when the engine is kept hot. Maybe this is the missing link. Maybe QF is wrapping their stoves in insulation to get the burn times up.

Hot Coal's is going to lose faith in me if I switch my opinion on "The Fan Effect".

Back to the drawing board. Ok. E=MC2.....

MnDave
 
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