That statement is what I took as sarcastic because lately I have been expressing my dissappointment in the fact that I am getting only half of the QF 5700 advertised burn time.
I honestly do not understand the soapstone efficiency claim. I saw a graph of surface temp vs time for a given input. Plate steel got to 900F, cast 800F, and soapstone 700F. Surface temperature correlates directly with efficency. How can PH claim an 81% efficiency? How can any stove claim an 81% efficiency?
MnDave
I know you have been disappointed about the burn times, but you have been asking lots of questions, and interacting with lots of folks, and trying different things to try to get where you would like to be in burn times (or approach where you would like to be), and I have enjoyed following your activities. I am interested in wood burning stoves, and take an interest in the various stoves, their pros and cons. Although you have not gotten the advertised burn times ( a disappointment), it has seemed as if you are finding corresponding with others about the problem, and working with your stove, an enjoyable occupation. And it will be interesting to see what you are able to achieve with the various tweekings, and will also be interesting to see what if anything your stove manufacturer can add to the discussion. So, I am indeed being sincere when I say that it seems as if you are enjoying the stove and I wish you a good burning season. I see why you thought elsewise, and I am sorry to have used ambivalent wording. I really do hope you get everything worked out so the stove in the end functions well for you.
After the holiday season I will call and talk with the folks at Woodstock, who will have, I am sure, the answers to our questions re the Progress Hybrid...hard data, I mean. I can tell you that I did burn a Fireview for a long time, and it was a great stove...quite small footprint, but put out a lot of heat for its size, and was very pretty and easy to use. It did not burn a lot of wood, either. Cat stoves are generally tested to be about 10 percent more efficient than secondary burn stoves, because (I'm sure) they burn volatile gases sooner and longer, so less potential heat is lost up the chimney. Then too, with Woodstock, the soapstone is quite thick and stores and slowly releases a lot of heat. And the stove can be burned very slowly, so not much more heat is produced than can be radiated out the window and/or absorbed by and later radiated from the stove...some is, but a lot less than if the stove was burning hotter. One can burn the Fireview at over 500 degrees stovetop temp, in which case a lot of heat is thrown by the stove, and the stoves needs to be reloaded about every 8-10 hours. When one does this, ones gets more BTUs per hour, for sure, but at the same time I'm sure a fair amount of heat is lost up the chimney (and the hotter flue temp supports this). When one burns with a slow cat fire, the flue temp is quite low, the fire burns a good 10-12 hours (or longer on a full load), and a soft, warming heat is radiated and keeps a good sized home very comfortable. But it won't heat a home over 3000 square feet to a comfortable temperature on cold winter days. Hence the Progress Hybrid.
The Progres Hybrid is designed to burn in either cat, or secondary mode, or in cat and secondary mode at the same time. The stove itself switches from the one to the other throughout the burn, and at any given time will burn in the mode that is most effiecient at the time. The stove supposedly achieves about ten percent greater efficiency than the Fireview, and it has a bigger firebox than the Fireview.
My experience with the PH leads me to believe that I am getting way better actual heating efficiency than that, compared to the Fireview. I have a large home with lots of windows in a cold climate. The Fireview simply could not heat my home. The PH does so with ease. Burn times on 1/2 or so loads are easily 12 -16 hours with good hardwood. It quickly gets the stove room's temps in the mid to upper 70s (stove room 16 x 46), in an open floorplan home, and with the use of a small desktop fan distributes heat satisfactorily to the second and third floors, with the second floor being in the mid to upper 60s, with a footprint of the home of 46 x 32 square feet. I believe that the great heating and low amount of fuel used to achieve it are a combination of the hybrid burning technology, the long air path in the stove, the large catalytic converter, the mass of the stove, and the angled secondary air fireback, that is very similar to a Rumford fireplace, and throws a great deal of heat through the very large window. The heat is thrown through the window, instead of going up the chimney. That's what I think. Way more heat is being produced than can be absorbed, the glass stays crystal clear even on a very low burn as long as the wood is dry, and the heat just pours out the window. It is too hot to stand three feet or so from it, but very comfortable once you are five or six feet away. The sides also radiated a lot of heat, as does the top, but nothing like the heat that comes out the window. If it is bitterly cold out, one can dial up the stove, and still get a very steady burn, just at a higher temp, which since it is burning more wood, throws more heat, and burns the load more quickly. But still, that generated heat is pouring out the window.
Last year I weighed a few loads of Ironwood, and posted burn times and temps, because people were doubting owners' reports. They were pretty impressive. In a few weeks I'll load the stove full with wood approaching the correct length for the stove, and record weight of wood, burn times, house temps beginning and end, stove temps, etc. Will see what kind of burn time I get. Will try this twice, once with a slow cat fire, once with a hotter combined fire. I've never loaded the stove full. I seldom burn with a stove top temp over 350, and have only once gotten this stove over 500, and that was really trying to do so. It burns at a low temp while throwing all that heat. I couldn't be happier with the stove. It is wonderful for my application and needs. It is a new design, and as with any new product, it has had a few things that have needed to be adjusted, but Woodstock was very open about the fact that they were pushing to get the stoves in homes to see how they functioned in the real word, and has been very quick to react to and correct/improve any issues/problems that have arisen, and has updated all the stoves with the improvements at no cost to the purchasers. A great company to work with. Couldn't be happier.
It will not burn as slowly as a BK - they can be reduced to an output of just over 9000 BTUs, while the PH can't get much under 12000. I'm guessing those stated figure are for a full load burning as low as possible, but maybe not...maybe for a small load. I burn a very small load shoulder season. Just a few pieces of uglies. That's another question I'll ask Woodstock when I call. Just out of curiosity, I'd like to have some more burn data. But for all practical purposes, I know what the stove can do.
Don't know if that answers any of your questions? If/when I get data from Woodstock, I'll post it.
Am interest to hear what Quadra Fire tells you.
Best wishes.
! I watch netflix. I haven't seen an ad in a long time. It's mostly gimmickry to get people to pay too much for something they don't need. 
