How quickly does the stove warm up?

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With that in mind here's the back end report.

7:30 am: stt 125 with blower on low all night. Hottest spot on the sides was 175. House temp 71 and 59 outside.

Another successful load.

As far as wasted heat & flue temps go that would be my biggest complaint with this stove. But as web said the flue stays clean so at least its not a total waste. But strangely so far this year its been running a little cooler. Maybe the probe is going bad or the pine perhaps?
I know they have this "heat life" in the stove. But 125 degrees just wasn't enough to beat my space after all night or being at work all day. It was still warm, but not heating really. It would take a few hours to get the house warmed back up. With the BK I've still got wood in the stove by morning. The stone was pretty, but it wasn't for me.
 
I know they have this "heat life" in the stove. But 125 degrees just wasn't enough to beat my space after all night or being at work all day. It was still warm, but not heating really. It would take a few hours to get the house warmed back up. With the BK I've still got wood in the stove by morning. The stone was pretty, but it wasn't for me.


I agree 125 isn't heating very much. What would it have been without the blower running? I don't know...and I have to run them to get any heat in this house. I also provided the outside temps to show that the load wasn't that heavy. When temps drop more I'll be starting fires at 5 and reloading before I go to bed.

I would love to have a BK. But when I got this stove they didn't have a good looking stove. And the closest dealer is 3hrs away. I might already have one but that dealer didn't think the Ashford had as much max heat as the Mansfield.
 
Want it hot at the front end, steel stove. Want it still hot at the back end,. rock stove. Kinda some physics involved.

I went from a steel non-cat insert to the stone non-cat. I always liked that back end warmth and if you kept it warm it did even out the peaks and valleys of heat associated with a steel non-cat. I decided that rather than depend on the stove material to do the job of heat regulation, perhaps a longer burning fire would be better. Keep the fire burning non-stop and the warm up time is of less importance. You just need a stove that can run low and slow.
With that in mind here's the back end report.

7:30 am: stt 125 with blower on low all night. Hottest spot on the sides was 175. House temp 71 and 59 outside.

Another successful load.

Good job, on that small load of fuel?
 
One data point. All of the below with the fan kit "off", and the fan down the hall on the floor "off".

There is a fly in the ointment. Instead of an infrared thermometer with an emissivity adjustment I own a dedicated infrared tire pyrometer with the emissivity permanently set at 1.0. It does fine on flat black surfaces, but can't be trusted on shiny surfaces. I dithered for two days on that decision, but ultimately when I pulled my car into the pits back when I was tracking it I didn't want to have to double check the emissivity setting before measuring my tire temps.

But I do have a black eco-fan sitting right over the cat on my Ashford 30.

I loaded the stove around 0600 this morning, one trip from the garage with a cloth firewood carrier thingy from Kroger. I got home around 1600, about ten hours into the burn, the house was +74dF, Fairbanks is "warm enough to snow" this weekend. I turned the tstat up from low to high, kept the house at +81dF from 1600 to 1845ish. I took the picture below at 1851, just before I flipped the lever from engaged to bypass. My comfort zone ends at +85dF, my wife's starts at +80dF, so +80-85dF is our sweet spot.

At T=0, base of the eco-fan read +209dF as pictured. At T+2 minutes I had the door closed on a fresh load of splits, eco-fan base read 208.5. I ran in bypass for a few minutes to get the new splits ignited, read 204.5 at T+9 minutes when I re-engaged the cat. At T+19 minutes, ten minutes after re-engaging the cat I read 252 dF. At T+32, 22 minutes after engaging the cat 319dF.

The smog police on a hot reload might have detected anything coming out of my flue for seven minutes total. I can't see the plume from my Ashford 30 with the cat engaged, but I can see the plume from a neighbor's oil burning furnace just fine in what light I have to work with tonight.

Tomorrow I will burn down the coals pretty aggressively so I can shovel some ash out of the box, see how cold the eco-fan base gets and how long it takes to heat back up on a warm rather than a hot reload.

Also, I will be shutting down the Saturdays after Tgiving and Xmas so I can keep my pipe brushed out. I expect my pyrometer will read the eco-fan base very close to room temp when the stove is cold, but I don't know how fast it diverges from reality as the fan base warms.

On a cold start I anticipate a cat-engaged clean plume at 22-25 minutes, but I am very curious to find out how much longer after that time has elapsed it will take to heat the fan base back up to the 209dF starting point.

Interesting thread, I would love to see a pre-EPA smoke dragon in here and know that's what I was seeing.
hotreload.JPG

PS: That tiny bright spot on the vertical portion of the fan base is the indicator from the pyrometer. It just barely shows up, red dot. I'll try to do better next time. EDIT: When I hold control and tap "+" a few times, then accept the option to view image full size the red dot shows up pretty good.

EDIT II: At T=63 minutes the fan base reads 364dF and the living room is up to +85dF. I turned the air control down to medium and all the fans back on because it is time to go out in shorts to shovel off the driveway to cool off a little bit so I can stand to be in here.
 
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EDIT II: At T=63 minutes the fan base reads 364dF and the living room is up to +85dF. I turned the air control down to medium and all the fans back on because it is time to go out in shorts to shovel off the driveway to cool off a little bit so I can stand to be in here.
That's crazy hot inside. I don't like getting over 75F. Oh well, this may be the only time of year you can get outside in shorts and not get bug bites so enjoy!
 
We don't run an epa stove. We have a 1,000 lb cook stove. I think that counts as high mass, right?
I can light a fire and have heat in a couple of minutes. It will throw heat in 5-10 minutes.
I never liked a slow stove.
 
That's really good. I had an old cast iron cookstove in a cottage I used to live in. It took over an hour before that stove started radiating serious heat.
 
I think if you push primary air to try to build quick SSTs in a stone stove you are wasting a bunch of fuel. If you get the firebox up to temp and then throttle it back with the intent to have a good clean fire with strong secondary burn, SSTs will respond in time. I let whats happening in the window tell me what to do with the lever and have the thermometer just to make sure things are not out of control. Back on topic here, maybe tomorrow it will be cool enough and I will time a fire from dead cold. 82 and mosquitoes yesterday::P so lots of warmth still in this drafty house.
 
woke up this morning at 530am and it was a little chilly in the house (54F) i knew the wife and kid wouldn't like it so i got a fire going to get the chill off. 38F outside but will probably warm up to the lower 60's today, love fall temp swings. got the coffee made and touched off a load of kindling set inthe magnolia log cabin style at 6am. left the door open about an inch for the first 5 minutes or so to get it rolling then closed it up with the air control fully open. by 620am the kindling is fully engulfed flue thermometer temp is at 350F (magnetic on single wall pipe not accurate i know but a good general guide) and the stove top thermometer is climbing to 300F. loaded in 3 small splits of yellow birch NW and put another on top EW. at 628am stove top is 400F turned the air down to 1/2 and watch the secondary show, never ceases to amaze me. 631am stove to temp is 500F pushed in the air control about another 1/2 inch room temp is up to 60F. at 634am i've got the air control closed down to about 1/4 open stove top is sitting around 550F house is warming up nicely. so all in all not bad 35 minutes or so from a dead cold start to warming up the house.
 
This morning's load is ash on a bed of poplar kindling . Took about 30 min from start up ( stone cold stove) to 450* with secondaries firing nicely in th summit. House was 68 f and is now at 71f. I mostly have ash to burn thus year as EAB is just killing it off all around me, anyway it's good stuff
 
It's been mild here, daytime - and sometimes night time temps too - around 10 C (50 F). Today it fell just a couple of degrees below that, so by lunchtime I decided to light up as the cottage temp (Now losing the warmth from last night's burn) had fallen to just below 18 C (64F), which is my signal to either light up or turn on the boiler.

I've got a smaller stove than most of you, (Jotul F3) so I guess it will get to temp more quickly than a bigger stove.

I am a top down lighter... Some Eco bricks sitting on a few sticks, so air gets beneath.. Topped by some small birch splits. then a couple of layers of kindling on the top. I use a wax and wood shavings firefighter on top of that.

1.30. Light up.

image.jpeg
1.40. The two layers of kindling are flaming away and there's signs of the fire reaching right through the small birch splits, to the Eco-bricks at the bottom. I've closed off the light-up air intake. I know, because of the wee creaking sounds the stove is making, that the stove top is up to at least 200, ... But I check anyway and for sure it's hitting 200.
image.jpeg
1.45 and all the layers are flaming, the stove top is hitting 350 and climbing pretty fast due to the quite strong winds that have just started outside. Secondaries have appeared. I shut the primary air by a third and stay close by...
image.jpeg

1.47 Stove top is already approaching 450, so shut down the air to half.

1.55 stove is up to 550. Primary air now 100% closed.

2.00 and she's dropped down to 500, which is how she'll sit for the next hour before starting to fall off.
 
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Yes, radiant stoves with good draft will heat up quickly. Our F3CB was a willing heater too and IIRC I could have the Castine up to 400F and radiating heat nicely in 20 minutes.
 
Played around with the Omega data logger this morning, to see how long the stove took to heat up. Loaded the stove with some pallet wood and kindling, added a fire starter and lit it with a propane torch.
15 minutes later the stove top is over 500::F.:ZZZ

DSCF1205 (Medium).JPG
Heat Up time_1.JPG
 
Here is how mine went this AM. 43 outside and 67 in. No thermometer in the living room with the stove and the thermostat has a wall and a staircase between it and the stove. Mine is a rear vent so the top vent block-off is metal. I measured temps on both for fun. Started at 6 AM news paper and kindling with 3 small cherry splits. Primary air full open and side door cracked. 6:02 closed the side door. 6:08 paper gone and kindling settled so added to more cherry splits. 6:10 firebox full of flames with stone temp just moving and metal block-off at 200. By 6:12 creaking and ping told me to try to back off the primary some with stone 100 and metal 300. 6:14 went to 1/2 on primary air and had 100/350 stone and metal. 6:16 tried to go to 1/4 bu t was a little early. 150/400. 6:18 150/500. 6:20 went to 1/4 175/525. 6:30 250/600 6:40 hall temp to 68, living room nice and cozy 300/600. 7:00 400/600. 7:15 added 3 more small/medium splits and opened back up to 1/2 425/575. 730 back to 1/4 or a little less and 450/700. 8:15 475/650 and really just a big mess of coals. 9:30 left for church 400/400 and 70 in the hallway. 1:00 back home and 200/200 and 71 in the hall.

This was a fun experiment! I have never really paid that much attention to how the heat cycle works on these things so it was pretty cool to intentionally watch and measure that much. I have complained about the cherry a little lately so I checked a few splits and got 10 -12%. I had at least one in this batch that was sizzling a little so not all is that dry :) The stove was never over 1/3 full and stacked pretty loose. I could have pushed harder earlier or used hotter fuel but I am not sure the stone temp would really react much faster. If you were really pushing hard trying to drive SST on the stone, would it be possible to over-fire the internals before the stone could react?

Also, that metal plate really responded fast...just like all of your metal stoves :eek: I sure can see from posts above how if you need quick heat, the metal stoves get there quite a bit quicker. crusing fire at 20 min and nice radiant heat out of the glass but decent SSTs are 45 man or so. I still love my big chunk in the living room though:p
 
Played around with the Omega data logger this morning, to see how long the stove took to heat up. Loaded the stove with some pallet wood and kindling, added a fire starter and lit it with a propane torch.
15 minutes later the stove top is over 500::F.:ZZZ
Do you always burn pallet wood?
 
Let the Ashford 30 burn out today. Crazy warm out, like +33dF, I got growing icicles off all the gutters and snow coming down in big heavy flakes. Brushed out the flue while I had a chance.

Cold start at T=0, ambient room temp and tire pyrimeter temp of eco-fan base (as in previous posts) +75dF.

I loaded about a half box of birch at 18%MC, but stacked real loose for good air flow. Some plane shavings for starter, then about 20" of kiln dried 2x4 in there as kindling. BK is very much against burning kiln dried lumber scraps for fear of overheating the stove. I am fine with that, I understand the chemistry; starting at +75dF I have a ways to go before I have to worry about overheat.

I had the cat engaged at T +20 minutes flat, a new record for me. Clearly a loosely stacked load with plenty of kindling is the way to get up on the cat. Base of the eco-fan was +93dF when I engaged the cat at T +20 minutes,.

I got all the fans off in the house, just trying to get the stove hot. Looking for +209dF on the fan base....

+122dF at T +30 minutes.

+181dF at T +45 minutes.

+256dF at T +69 minutes, got distracted, turned all the fans back on.
 
I don't know the moisture content of the dry doug fir we are burning right now but without trying I am getting secondary combustion in 10 minutes and full air shutdown in 15 minutes with a clean hot stack and a 400+ stove top. This wood is too dry IMO. 6-8" split take off like they are kindling.
 
I have been getting secondaries in about the same amount of time as bg with well seasoned ash stone top is generally in the 450-600° range in 30min or so. It has been unseasonably warm here also
 
12 minutes to full shutdown of air this morning on a start from a few coals and a 110F stove top. This wood is crazy dry. Burn times are 8 hrs max, regardless of split size.
 
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