I get about 7 hrs.I aim for 350 on the pipe and 600-650 on the stove top. My issues are with secondary burns, they only last 10 minutes tops and I never get those slow lazy flames people talk about. If i close the air all the way i get dirty glass and if i dont use the bypass i'll get smoke out the door. Thinking my 12 ft chimney is a little short so im planning on adding another 2 feet and seeing if that helps.
The reason you have to use the bypass is the baffle is designed in this stove is larger and comes out towards the door more leaving just a small space for the flue gases to escape. This makes the smoke have to travel a further distance over the baffle manifold that the secondary preheated air is coming out of to ignite the smoke gases.
This stove does burn dirtier than a more insulated firebox type stoves. This is a known trade off to make the stove be able to radiate more heat. This stove even tho it burns a little dirtier at 5.7 grams emissions still meets the current EPA standards which is 7.5 grams emissions or less.
The input air control from everyone I have seen info from who have these type stoves from SBI , have reported that the air control is able to shut the air down to a low level that snuffs the fire. People have to learn their stoves to see what level the can turn down the stove and still have flames or secondary burns.
Since this stove radiates heat so well your most likely trying to shut it down further to lower that heat output as it can run you out of a small room or even a medium sized room.
Here is something to think about you can keep the input air open a little more and not worry so much about the longer burns as this stove will continue to put out alot of heat at the coal stage since the firebox isnt as insulated. Focus more on what your home temps are in the mornings. As all that heat is getting into your house even if the heat cycle curve is a little different over time.
The reason you dont have to worry as much with this stove how long you have burning flames is that the stove seems to always have coals left for restarts which is the standard most people to gage how long a burn cycle is for a stove. As do they have enough coals to restart with out the help of a fire starter.
I have had coals for re-start in my stove at 13 hours. But I normally reload at 8 to 9 hours.
If you want longer burn times try doing east west loads instead of north south loads.
I too at low input air levels just get a small amount of flames coming off the wood and not very much secondary action.
Take note of this as seems like all stoves have this behavior. If you load the stove fuller so there is a small amount of space left between the secondary air baffle manifold and the tops of your wood load. This small space acts like a miniature burn chamber being much easier to heat up and maintain the high temps for secondary light off and keeping that secondary gases burning for longer period. I?f your only loading your stove 3/4 ways during these warm weather that maybe why your not getting as much secondary action.
Another aspect of getting secondary action is how fast your getting temps up in the stove to get the input air shut back down. As its the shutting down of the primary input air that cause more air to be pulled from the baffle manifold into the firebox. As the draw of the flue is the main driving force of pulling air into the fire box. If you shut down the primary air down then the only place left for the suction draw of the flue to pull in air is that secondary baffle manifold. The best way I know how to explain this is if I reload to a full fire box with only now that extra small space left up there in the firebox and I reload on extra hot coals in this stove as this stove is very controllable so no chance of a run away stove, then if my wood is good and dry and the firebox is already nice and hot and has a hot bed of coals the wood starts off gasing quick and secondary burn happens quickly so I get a long time I see secondary burning. Now if I have to keep the bypass open for a long time and keep the door cracked open for a while as my wood is not as dry as it should be then the temps dont come up quick in the firebox and I will be burning alot of the wood just getting temps up in the stove and by the time I get the temps up I am not going to see as much secondary flames for two reasons first being alot of the gases in the wood was used up getting temps up in the stove and second the little bit of extra moisture is killing temps in the top of the firebox thus killing secondary flame action.
I always say the 20% moisture or less should really be 18% moisture or less. Alot of stove problems is from wood that is close to being dry enough as it will burn but its a pain in the rear. And the stove operates sub par. You get alot less heat out of the stove from the robbing the secondary burn quality.
I have my stove in a 27 foot by 27 foot large open family room in the basement and I have french doors that I can open into the rest of the basement if I need to vent heat as these Drolet Myriads really put out the heat. I tend to want to damper my stove down alot also but the secondary action isnt as good.
You might try splitting your wood one more time a few pieces and measure the moisture content on the inside using a moisture meter. I would be curious of what it is.
My wood is like I am speaking will burn pretty good but not ideal. I have had a few loads of some good stuff I have found and the secondary action is so much better with really dry wood loaded on a larger hot bed of coals.
