For those who do care what others say, here are some facts (Inconvenient things, facts. But useful for some):
Oak has about 7500 btu per pound. The Oslo is rated by Jotul for a maximum output of 70,000 btu at an efficiency of about 75%. To achieve those 70,000 btu output will take 93,333 btu input. Oak has about 7500 btu per pound, so for each hour at maximum output you will need 13 pounds of properly seasoned oak. If you are using oak "seasoned more than a year", you will not obtain anything like this output as it takes three years after being cut, split, and stacked to be properly seasoned.
So if you can somehow stuff 40 pounds of oak into an Oslo, you can, in theory, go three hours at maximum output - which would be a stove top temperature of 550 to 600 degrees. 40 pounds, 7500 btu per pound is 300,000 btu input, 225,000 btu output, 70,000 btu per hour for just over three hours. At that point there would not be a single atom of wood left. It is obviously not possible to burn a load at maximum temperatures to the last atom of firewood, therefor expecting four or five hours of 550 to 600 deg. stove top temperatures on a single load is fruitless - it is not in accord to the laws of physics. This is not in any way affected by the price of the stove.
More reasonably you will load perhaps 30 pounds of wood on top of a bed of coals and generate maybe 50,000 btu during the first hour, 30,000 or so the next couple of hours, and less than 10,000 btu in each of the last two hours of a five hour cycle.
For those who need longer burns at higher btu outputs there are larger stoves.
Heres some more facts that we should also mention: Of course taken from Jotul N.A website.
"it will burn for almost 9 hours"
I loaded mine, packed tightly full, just 3 hours 41 minutes ago, theres hardly a red coal left…….I would love to see how they call it a 9 hour burn!
"70,000 BTUs per hour" - Not a chance!
"patented spring loaded door handle" - Thats the same one that doesn't work after just 6 weeks, even a brand new one didn't work
"easily extend burn times with Jotul's single control lever" - I tried that earlier and my temperatures still kept increasing and increasing, without my control.
I reckon hearing this too is inconvenient for some.
So lets ask, given those facts,
Q. What they define as "burn time"? What temperature is the lowest, and obviously maintained for 9 hours.
Q. Under what conditions did they get that burn time of 9 hours and was it repeatable?
Chimney Length
Insulation quality
Outside temperature
Log condition seasoning/split/stacked/species
Home size, ceiling height
Weather conditions at the time humidity/pressure/wind/temperature
etc
Q. When they reach 70,000 BTUs how long does it stay at 70,000 BTUs and what was the burn time then once 70,000 BTUs is reached.
Q. Can it heat a 2,000 square foot home, in New England, for 9 hours, at 70,000 BTU's?
If not, then for how many minutes can it heat a 2,000 square foot home at 70,000 BTU output in a New England winter.
Without answering these facts that they state, then its just a pile of gibberish nonsense that comes at a significant cost to the consumer and is deliberately misleading and the cause of a lot of frustration.
