I know a ton of varibles here but comparing an overnight burn compared to a "I want heat" burn how much primary air do you give your stove, 1/4, 1/3, 1/2, or more.
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For overnight or "want max heat" burns, I run the primary the same way (closed as far as it will go). The difference is that I will let the firebox heat up to a higher max temperature before slowing it down with reduced primary air when I want "max heat". That results in a hotter peak temperature and a slightly shorter burn time.
In the past before learning the stove we burned it with 2/3 open for the HI300. But have learned that like DBoon pointed out, we can get about the same heat just letting the box get a bit warmer at first and then using 1/3 or 1/4 the air. The heat output is less, but the amount of wood consumed is far less. Our first method went through about 175% more wood per evening compared to the 2 degree "loss" in temperature difference we realized in the living room. First method had it at 75-77...this way 73-75...too hot for me, but the better half loves it and is willing to put up with my obsessive hobby so its bearable.
Depends on the wood and the flue. With our stove, burning fir, the air control all the way closed will still see the stove top hit 700+ with the right fuel charge. Burning cherry or locust, about 1/4 open works better if the goal is high heat.
My stove doesn't have separate controls for primary and secondary. The primary air is essentially the air wash for the glass and fed via the same control as the secondary burn tubes. Now, the amount of air going through the burn tubes are limited by the size and number of holes both of which are fixed. Any surplus air goes to the down wash and if it has sufficient force to overcome convection, becomes primary air.
The doghouse (zipper) air is fed from another source that on a stock RSF is a fixed size but mine is adjustable. I set it to minimum most of the time.
For maximum heat output, if I go by the gradients on the scale, I set the primary/secondary air to 1/4 but based on the overall range of motion of the lever, it is 1/2. Now, my stove has a bi-metal thermostatic control so it takes over from there and provides more or less. For overnight burns, I set it all the way to the closed position but the EPA mandated a notch in the butterfly so it isn't fully closed.
Both day and night, I regulate the amount of heat by the frequency and way I load/stoke the stove.
The doghouse (zipper) air is fed from another source that on a stock RSF is a fixed size but mine is adjustable. I set it to minimum most of the time.
For maximum heat output, if I go by the gradients on the scale, I set the primary/secondary air to 1/4 but based on the overall range of motion of the lever, it is 1/2. Now, my stove has a bi-metal thermostatic control so it takes over from there and provides more or less. For overnight burns, I set it all the way to the closed position but the EPA mandated a notch in the butterfly so it isn't fully closed.
Both day and night, I regulate the amount of heat by the frequency and way I load/stoke the stove.
Oldspark,
Did you find any difference in how the stove operates with that EBT plugged up?
The difference for me between a low overnight burn and high burn is only only about 1/2" on my air setting controls. It helps to have notches or numbers on it for guidance.
Did you find any difference in how the stove operates with that EBT plugged up?
The difference for me between a low overnight burn and high burn is only only about 1/2" on my air setting controls. It helps to have notches or numbers on it for guidance.
Oldspark - I'm similar to a post above - I have to shut the primary all the way, and pipe damper to half most of the time, in order to let the fire cruise at a reasonable temp and good burn time. I simply can't leave my primary open at all, in almost all cases (excepting perhaps at 1/4 open with a full load of oak, but that's only until the load is really going, I close completely once the secondaries are really flowing). Cheers!
Not much if any, I assume if my chimney drew a little better I could easily get to 700 stove top, the way it is now it takes some time and the flue temp is a limiting factor as it hits 600 (surface temp) with the stove top still at 400. I should try the damper but I know my draft is not too strong I think it is too weak to get the high stove top temp. I just dont feel comfortable running the flue temp much above 600 even for a short time.Todd said:
sparky, no damper needed. The flue should be rated for ~900F continuous operation. A 15 minute foray up to 7-800 is safe and within spec. Let her rip if you want to get all 97K btus out of the stove. Ya can't complain about a horse getting up to speed while pulling back on the reins. Once the initial bloom of wood gas is burned off, she will settle down to 4-500F stack temps with a 700F stove top.
DBoon said:
Same here, let 'er rip a while longer before dailing it back if I want/need more heat.
I have a surface mount sensor so the internal temp at 600 surface is going to be at least 1000 or so correct?BeGreen said:
I agree with the let her rip post. Keep an eye on your flue temp but as Be Green pointed out you should safe above 600, you probably have not even cured the paint on your flue yet.
Now what was that about plugging up the EBT?
Now what was that about plugging up the EBT?
I am seeing 600 surface mount temp which is at least 1000 internal temp and I think that is what the chimney is rated for, if I run it up to 800 surface (which I think is possible) temp that will be 1200 or more internal temp, thats above the rating of the chimney.
Todd suggested disableing the EBT so less air and maybe a lower flue temp, did not seem to make a difference, I believe BG didabled his for one reason or another.
Todd suggested disableing the EBT so less air and maybe a lower flue temp, did not seem to make a difference, I believe BG didabled his for one reason or another.
I have a Summit also and I am not able to get the stovetop over 560 no matter how I have burned. I have tried what I think is everything and have yet to hit 600 stovetop. I can get it to cruise at about 525 but that is about the limit. Been Burning 3 year seasoned oak. I also have the flue temp issue. The flue heats up much quicker than the stove. The best way I have found around this is to load with air only 1/2 open and things are much more in control and when I start turning it down, I only move it about 1 width of the lever with each adjustment. I wonder if anyone out there with a summit is actually getting 650 stovetop temps.
oldspark said:
It's approximately 50% higher or 600 surface = ~900 internal. That is if the thermometer is accurate. Try moving the thermometer up 6" and see what it reads. Or take it off the flue for a week and just run the stove for heat. See if it seems to run better
PS: Hasn't this been discussed an awful lot already? I'm getting deja vu all over again.
https://www.hearth.com/talk/threads/63355/
I've learned MAX heat is when you close down as much as you can and have secondaries firing. My stove manual states do not fully close damper with blower on. I fully close it with the blower on and the secondaries are burning real nice for 3 hours. This tells me the stove is not starving for air because of a good draft. If you are running stove open with secondaries firing, you are sending more heat up the stack. As soon as the secondaries fade, I'll start opening up the draft. With overnights, I leave draft open about 1/2".
Heh heh heh yes it has but my question in this thread was about the setting of primary air for max heat, some how it went to flue temps again. I have a IR gun so I am in the ball bark and 600 flue temp is not a problem I run it to that a lot, its going past that to get the stove hotter is what I do not like. lillyrat sees pretty much the same thing as I, I think it is just my chimney stove combo and have to live with it. I might do something different with the chimney next summer.
To get max heat out of my stoves, I let the flue temp get up to 900* before cutting the primary air back to about 5-10% open. Seems very similar to alot of other guys here.
do you have an IR meter? If so, run it all over that stove pipe. I was amazed to see that I'd have as much as a 150 degree difference going 90 degrees around the circumference of the pipe in places. I think you'll also see it drop off quickly as it runs up the stove pipe. My thermometer is sitting just above the ridge on my stove pipe now and reading 500 degrees, but go up 2 feet to my 90 elbow and it's down to a little under 400.
Additionally, I use my flue temps (especially my probe) as a means of predicting what my stove is going to do next. My stove top temps heat up much slower than the chimney. At the end of the day, my goal is to keep the stove top under 750 max (700 is the typical "redline"). So I simply use my flue thermometers to help me predict if I'm heating things up too quickly or not. I don't generally allow them to dictate the total stove temp and as a result there are times that my probe thermometer will sit there at 1100 w/ my stove cruising just fine. Nothing is glowing, I do this regularly, I never smolder the fire, therefore there is nothing in the pipe to start a chimney fire and I haven't found a reason to be concerned since my stove top temps are within what folks at my stove co recommend. If folks at englander say it's OK to hit 700, then it's OK. I haven't found a way to do so w/out letting the flue get warmer than what condar thinks is acceptable. But through my research, I'm convinced that their probes read too high for read world settings.
In all, I think you should be less concerned with your flue temps and more concerned with your stove top temps. Considering the wood you burn and the care you give into paying attention to maintenance, you have nothing to worry about IMO.
pen
Additionally, I use my flue temps (especially my probe) as a means of predicting what my stove is going to do next. My stove top temps heat up much slower than the chimney. At the end of the day, my goal is to keep the stove top under 750 max (700 is the typical "redline"). So I simply use my flue thermometers to help me predict if I'm heating things up too quickly or not. I don't generally allow them to dictate the total stove temp and as a result there are times that my probe thermometer will sit there at 1100 w/ my stove cruising just fine. Nothing is glowing, I do this regularly, I never smolder the fire, therefore there is nothing in the pipe to start a chimney fire and I haven't found a reason to be concerned since my stove top temps are within what folks at my stove co recommend. If folks at englander say it's OK to hit 700, then it's OK. I haven't found a way to do so w/out letting the flue get warmer than what condar thinks is acceptable. But through my research, I'm convinced that their probes read too high for read world settings.
In all, I think you should be less concerned with your flue temps and more concerned with your stove top temps. Considering the wood you burn and the care you give into paying attention to maintenance, you have nothing to worry about IMO.
pen
BeGreen said:
That 50% is bogus. With the Condar probes it's more than double and has been proven by many here before. I think even Wes999 used a digital thermo couple and it showed at least double the external temps. 600 external sounds too high imo. I may have a different stove but I rarely get over 350 external pipe temps when my stove is coming up to temp. Only when I'm in the bypass mode do I come close to 600 and that is a direct path straight up the pipe. Maybe that extra heat going up there is by design for the Summit and settles down later and may not even hurt the liner, I don't know but I think I'd worry about it as well.
Well I'm still trying different things so maybe I will let the flue temp go up some more, you are right pen the temps vary a lot but I already moved the sensor up some, a lot of times the stove just likes to settle at 600 no matter what, it really slows down about 600 stove top.
I'm with you Todd, I just think the flue is too hot, not everyone agrees with me but I am use to it. Inner temp double the surface temp has been proven by members of this forum so I believe that is true also.
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