Hybrid Stoves

[begreen]

What I have read alot of stove manufactures measure the total stove interior space and that doesnt always equate to usable space.

If I was measuring side to side would be inside edge of fire brick to fire brick and to the top of the fire bricks as they say not to load it any higher than the fire brick in a NC-30. Then the front to back measurement would be from the inside edge of the doghouse air to the inside edge of the back firebricks. I would not measure all the way out to the door as your not supposed to load that close to the door.

Not to pick on NC-30's but I can not see a design difference in that stove that equates to such a low grams of emissions number it tested at. As alot of other tube stoves dont come close and they are basically copies of the NC-30 in design. A tube stove is a tube stove. Firebrick insulated fire box. A insulated baffle board. Burn tubes with preheated air injects into the smoke path just under the baffle board. I spoke to one manufacturer who said they bought one to see how they do it and they couldnt figure it out or get the same results in their own testing. I will just keep scratching my head on that one.

Ok I am ducking now , there went a firebrick over my head.

IIRC correctly, Quadrafire has achieved very impressive results with their tube design on their Millenium stoves @ 1.1 gms./hr.

 

[Huntindog1]

Oh yes the Quadrafire I like to keep an eye on their stoves as they are the ones that use a more insulated firebox (insulated firebricks) and they also have the automated combustion control which I think would give them better performance. Plus another aspect of their design is if you watch their quadraburn4x video you can see they have placed an over sized channel along the entire back of the stove at the coal level where your super hot coals would be during the burn cycle, this super heats the secondary air to a much higher temps , so along with a more insulated fire box and extra super heated air you can see where they are achieving the extra performance.

It may also be that with the quadrafire automated combustion control, simply what it is doing is when the stove gets in its hottest part of the cycle the control will automatically dial down the input air setting to keep the stove burning in a more even fashion. Its during these hottest peaks in other stoves that the extra heat will increase the air velocities thru the stove flushing more particulates up the flue. If you can keep the stove calmed down with an even burn rate thru the entire burn cycle you not going to stir up as much of the particulates and they will settle more in the bottom of the stove.

That brings up another point on the NC30 is they dont use an insulated ceramic blanket on top of their baffle board for extra insulation and some say there is a gap between the baffle board and side of the stove that people have various tricks to fill, now maybe the gap doesnt effect grams emissions numbers. First thing I would do if I owned a NC30 is get on ebay and get me a ceramic blanket and put up there on top of that baffle board and buy it over sized to fill in that gap everyone talks about. Dont get me wrong, englander is a good stove no doubt and a good company. Its a quality product and will last for years.

There could be one reason for the Englander NC30 good low emission rating is the stove is large just like the larger Quadrafire Millinium (1.1 grams) stoves have a lower emission rating than the smaller Millinium stove which is 2.1 grams, the larger stoves and specifically the NC-30 is a tall stove as in its got alot of head room in the top meaning there is more distance for the settled particulates in bottom of the stove to get effected by up top of the stove where the suction of the flue starts. Its like having a vacuum hose lowered down thru the top of the stove, if you just lower the vacuum hose a little ways down from the top your not going to suck up any of the dust and ash from the bottom of the stove but the closer you lower the suction of the vacuum hose down close to where all the particulates have settled in the bottom of the stove the better chance you have to get a few more micro grams of particulates to be sucked up. Plus you have air flows and fire turbulence stirring the pot also.

1 gram of particulates = .035 ounce not much to begin with. Its like voodoo almost as we are splitting hairs. So small changes can cut your grams emissions in half like say from 2 grams down to 1 gram as we are only talking very minuet quantities. Dont sneeze you'll screw up the test.

Quadrafire is where I got the idea to better insulate my stove.

,

 

[firefighterjake]

We shall see. It has been a long time since one of these got started here. It pretty much boils down to how the stove heats your house and how much it eats to do it.

But I will always pick on evangelists. Especially for stoves nobody has burned in yet.

Just don't drink the purple Kool-aid

 

[jharkin]

If absolute minimum grams/hour was the only criteria that mattered, we would all be running out to buy used Defiant Catalytics....

chirp chirp .... chirp chirp .... chirp chirp ...

 

[mellow]

Wow this got off track.

Back to the original thought about hybrid stoves. Thinking about this last night and seeing the BK design from 1983, I have come to realize that I guess you could call it "new" technology, all the previous hybrid stoves have the cat and the tubes in the same location, with the new hybrids it is separated.

So is BK going to be coming out with another Hybrid? What is your thoughts on them BKVP?

 

[Todd]

Well crap, the local Farm & Fleet didn't have a NC 30, so I couldn't measure the fire box. I guess I'll save that argument for another day.