Heat time vs. Burn time

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schortie

Member
Nov 6, 2008
243
michigan
There has been a lot of discussion on burn time and what that means to different folks. I'm sure the stove companies gauge burn time from the first flick of the match to the last glowing ember, but how long is that load actually heating your house? I would say on a medium load, I can achieve 500-600* for about 4-5 hours burning mostly ash. Just wondering how other folks do with HEAT time.
 
As Burntime :lol: it is pretty subjective. When its mild, say 30 out, I can get heat to maintain indoor temps for 6-7 ours tops. In cold, say 20 below, it will maintain for 4 hours plus or minus, then it loses ground. A lot depends on your insulation, windows etc...
 
I agree with burntime. Subjective. Many variables involved.

Depends on type of wood you are burning too. How full you fill firebox and how big your firebox is. How big your space is that you are heating. If you are using supplemental heat along with stove etc., etc.,

As others have said here - every load you burn is different.
 
I'm not one of those purists that absolutely refuse to let their furnace come on. In really cold weather, I set my furnace to hold at 71 and when I get up in the morning, the gas furnace is running with lots of coals still in the woodstove. The furnace only burns about $2 a day in gas.

I set the furnace overnight temp to 68 in milder weather but it is a setback and programmed to bring the temp up to 71 in the morning.

I don't know what the absolute burn time would be as I seldom go more than 7 hours before refilling. The amount of coals left is determined by how cold it is and how much ash has built up in the stove. My stove has a bi-metal thermostatic control so it adjusts the air to the demand. The wife tends the fire through the day and we both fiddle with it in the evening only stoking it full for overnight or if going out.
 
Though it's not likely to happen, I too would like to see some sort of uniform reference established (if only for discussions in this forum) of a readily (or even roughly) comparable heat time.

Offhand, I'd think that would only be possible - given the wild variance in stove design, performance and 'home environment' - by using internal flue temperatures measured at a specific distance from the stovetop.

With my own setup, I know that at a flue temp of about 400*, 12" above the stovetop, the stove is just beginning (or just finishing) radiation of 'usable' heat.

But that's just my setup.

Peter B.

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It definitely is a measure of the entire burn cycle time, but never called that.
 
My stove is a zero clearance fireplace so the SS chimney goes right into the top of the stove. There is no place to measure flue temp. No real practical place to measure the stove temp either. I move a lot of air across the stove so even air temp is a dubious measurement.
 
Basically with my soapstone stove I need to reload by the time she drops down to 300 if it's real cold or windy, usually under 15 degrees outside. This gives me about 6-7 hrs between reloads of usable heat. The stove will climb up to 650 after reload and slowly drop to 300 in 7 hrs. I could probably go longer if I wasn't heating from a basement and trying to keep the upstairs above 70. If it's 20-30 degrees outside I can go 8-12 hr burns and maintain same house temps.
 
On an average winter day (25 degrees) with an average load of wood (cherry/hard maple mix) stove throws useable heat (auto blower on) for average of 8 hours.
 
During day time temps of 25 and night time temps of 10 I can manage to pull off 6-8 hours of comfortable heat. With the stove setup in the basement I can manage to keep my first floor 71-73 and upstairs 63-65 using a good full load of red oak/white oak/cherry mix. In the morning i'll normally find stove top temps of 200-300 with enough coal to start the fire back up. I've been realy trying to figure out how long the flames last and notice that after about 4-5 hours most of the firebox is a mass of coals but still throwing plenty of heat.
 
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