"Burn times" are mentioned quite often and we see how it varies in different type of stoves. Obviously many factors contribute to it. To many its a big factor on purchasing a stove. Just was wondering what others consider as burn time. Is it producing enough heat to warm house or still having glowing coals for a quick restart. And everything in between What are your thoughts?
Burn time depends on who is talking... My stove is listed at 14 hours of burn time, but good high output when the stove's primary air is closed down for the longest possible burn means 2-3 hours of 600* flue temp then dropping back slowly on coals to 250 for 6-8 hours or so. It holds coals for 12-14 hours that will allow just stirring the coals a bit and re-loading the stove and it will be back up to operating temp in 5-10 minutes. That is walking away and not touching it. My stove is not a cat stove and has secondary air tubes. I burn dry wood. Ash, Cherry, Maple, Oak, Locust. Our house is a 2,700 sq.ft. Colonial with full basement with 6" thick walls and standard fiberglass bat insulation. The stove is at the corner of the house where the walk out basement door is located. Very convenient for moving in wood. When I am home, I typically rake the coals forward and put a split or two in every hour or hour and a half and leave the primary air at meduim or high depending on the outside air temp. This seems to work better when the outside temps are below 30*. Cat stoves I can't directly speak to, but from reading a lot on here, they seem to be more controllable and the large hybrids can acheive longer unattended higher stove top temps burn times. They also cost a lot more to bring home. I got my stove for under a grand 5 years ago. It is a large firebox inexpensive air tube stove. It heats our whole house from the basement but the furnace does kick on occasionally below 25* outside. It kicks on more at 15* but the stove is doing the bulk of the heating. I use the furnace blower to move the heat throughout the house. I know that isn't typically the most effective way to heat, but our set up here works fairly well and all the wood / ash mess is contained in the work room area of the basement.
Stoves are generally a bit smaller here, I guess it’s to do with the climate and the fact that houses are smaller. The manufacturer of the stove I have boasts about how it can ‘keep in’ overnight, whilst it can, in my experience very little useful heat is produced in doing so. You’ll get a few embers which make it easier to restart. So for me, burn time is the amount of time the stove will actually heat the house, however, there’s so many variables so it’s probably not so easy to quote these figures in practice.
When burn times are mentioned I can’t help but wonder why all the others can’t seem to match Blaze King and Quadra-fire’s longest burning models...dang near double of their nearest competitors...if they can actually burn that long. We’re talking 30 and 40+ hr advertised burns. Those are some substantial claims and some posts here...at least with the BK’s seem to report as advertised, though not much mentioned of Quads on this forum that I have seen. These are steel stoves that heat up quick and cool quick...claiming these long burn times. Those claims, coming from steel stoves, is nothing to sneeze at. Still there are plenty of well made stoves that do not advertise such long burn times. Many list 8-10 hours ...talking burn hours, not just residual heat holding ability of, for instance, soapstone. Not trying to poo poo on soapstone stoves by any means, but if those manufacturers of soapstone stoves would even slightly increase their burn times, beyond what they already are, then those companies would have a lock on the longest “heating” stoves made. I’m expecting big things coming from, at least Woodstock, with regard to longer burn times. May not be soon, but I think it’s coming...and I could be totally wrong. You add a longer burn time to the heat holding ability of stone and now we’re cooking with peanut oil. Their burn times are already better than some steel stoves...they just need to be increased more across all models, in my opinion.
The stove is an appliance. It does not have a brain. This appliance has performance specifications that it can achieve whether out in a field or in a tiny well insulated home. So no, burn time has nothing to do with how long your house stays warm and everything to do with how long the stove can make the user specified amount of heat. When your goal is the longest burn time possible you want a low burn rate, high efficiency, and a large firebox. Not all stoves can burn at low burn rates cleanly enough to satisfy the EPA. This is where the noncats and some of the poorly designed cat stoves fail as they are not designed to burn slowly. What if that low burn rate is not enough to heat your home? That's your problem, not the stove's. You can turn up the stove and lose some of the burn time, you can run the furnace, you can let the house cool, or you can buy a second stove. So the question was, what is burn time to you? To me, it is the amount of time that the cat meter reads "active" which is above 500 degrees. Sure, I can restart with coals remaining after the cat meter falls below the active line but the stove is making much less heat at that point. My truck gets 12 mpg towing and 21 cruising the freeway. It all depends on what you're asking these tools to do.
It's all about the burn rate. There are some very nice stoves that are made to make lots of heat and the design did not or could not prioritize the ability to burn at low rates.
Really interesting question and thread. I can only hold coals for about 8 - 9 hrs and that's with Oak, usually enough to restart a fire fairly easy. Burn time to me currently I suppose is stove kicking out enough heat to warrant the blower running and pushing hot air out. Generally in pretty cooler weather I wake to the blower being off and the house cooler which is understandable. Ideally I'd want a stove to still have some flames or a large hot bed of coals kicking out heat where I wouldn't have to reload until I left for work at 8AM. Load up at bedtime 9-9:30PM, next reload 7-7:30 AM....repeat, would be ideal. Someday!!!
Most extended burn times compromise heat output. Not much value to trying to get 30 hours of burn time if you're freezing your buns off to do it. Comes in handy during shoulder season, but come cold weather you need output baby. Most stoves that can do extended burns can also pump out the volume because they are bigger stoves to begin with. If they also are more efficient at sending fewer BTU up the chimney and also have a large firebox then they are also capable heaters. It's not rocket science. It's when you start putting some weight to the word budget and affordability and only need a medium size stove that the playing field gets interesting. If I'm doing batch burns then what I'm defining the end of a burn as is just enough coals to restart without having to go thru cold start procedures. If I'm tossing wood in to try to keep the stove "full" and pumping out the volume, then I could really cars less about burn time and usually care more about being able to keep up with heat losses.
Like others have said I basically narrow down "burn time" to being able to do a reload without kindling and just get the stove back up to temp reasonably quick. When I come down in the morning after a normal overnight burn and see my dumb little Eco Fan still spinning on the stove top, I know the stove is still within it's burn time.
You hit the nail on the head- when do we call the stove 'out' or 'out of fuel'? Stoves rated in 'burn time' seem to be a guesstimate and vary wildly depending upon the stove's manufacturer. Then the fanbois climb aboard and legends start, not that they have any basis in reality. The thing to really consider when looking at wood stoves is firebox size; the more fuel one holds, the more heat it will put out and with a modern, efficient stove, you can use that amount of heat at a relative low setting and produce a long burn time. But to rate a stove, any stove or wood burning device, in burn time without any qualifiers is really pretty foolish IMO. Brian
Been awhile since I looked at this thread, let alone looked back at what I said in its entirety. When I mentioned those stoves like BK, Quad, I just assumed people would think about those stove models touting those rates and then compare them to similar sized stoves, like the Kim Sequioa for instance...or another comparable sized fire box. For that matter, regardless of max burn times mentioned, I was also thinking about stoves with comparable fire box sizes having such different burn rates. That’s not a rebuttal of your comments, rather, a clarification of my own thoughts. I shouldn’t have assumed and just went ahead and spelled out my thoughts a little more clearly.
I don’t have time right now to highlight information from brochures, but there’s some big variances between firebox size and burn times that cause me to raise an eyebrow. There’s also a lot of factors to sort through and consider also.
There is allot more to burn time than just firebox size. The firebox is the fuel tank. Just because you have the same size fuel tank doesn't mean it will last the same amount of time. Some stoves can turn down further than others. Some stoves put out more BTUs per hour than others. The fuel tank just gives you a certain ammout of available BTUs. The stoves design and operation determines how long that load of wood can last.
I know you wasn’t disagreeing...but you did further explain my vague statement...and so I mentioned it. Vague for a purpose... It’s all good!
Marketing. Firebox on the 30 is stated to be 3.5 cuft. If you take out the firebrick, baffles, and burn tubes, yeah maybe. I don't burn mine that way. Wasn't designed for it. The usable firebox size is actually closer to 2.75.
