Production Woodstock IS

that's what I was trying to express

And only to help williaty

 

I agree. Throttling down the stove sort of gives the cat what it needs to take over. I do believe in running the stove hard up until that point. I normally take it from a fully involved fire at WOT down to notch 5. At that point I hear a whole lot of pinging and the temperature on the cat probe slowly rises. It takes some time to get past that learning curve.

 

That's what I do too. Get the fire cruising and then engage cat and turn it down.

 

Well, you all will have to wait for the continuation of my comedy circus until tomorrow, I think. I spent the day teaching someone how to use a large format camera and we just got back to the darkroom to start processing the film. I suspect by the time it's hung to dry and I've cleaned up it'll be too late to start the fire and then want to watch it for a couple of hours before it enters the "getting colder and not doing anything interesting" stage.

 

williaty don't feel bad we were all there at one point... you got a great stove once you learn it... you will be fine!

 

Agreed! Hang in there buddy.

 

I believe I have an overdraft problem. Once my stove gets rolling, there is no slowing her down. I'm currently at 650* stt, 1400* cat temps. I was a little worried about my cat getting hotter so I closed the draft down from 4 small notches to all the way closed, in hopes of calming down my secondaries. Now the stove is literally whistling at times through the air intakes. I used a magnet to try and further seal the secondary intake, but I still hear it sucking air and the flames are unphased.

I'm currently running 4' of double wall pipe, into 18' of class A up through my 2nd story, attic, & then roof. I ordered a damper to hopefully be able to control things better.

Do you guys hear air sucking into your stove? Should I disengaged the cat above 1500* to let more heat out the chimney and to keep from cooking the cat? Or Am I worrying too much?

 

The cat is always hyperactive when it is new. However, it does sound like your draft is pretty strong if you still have flames with the air choked. Call Woodstock about this ASAP. I know they have been working on some components for my friend who had the same problem and warped his stove.

 

As JA600 said the cat is very active when new and it's not uncommon to have the air set to the bottom of the scale. I usually run mine between 0 - 3 on the air setting anyway. I also have a chimney straight up though the second story and out the roof another 5 feet.

Try a couple things if you haven't already done so. Check your ash drawer to make sure it's closed tight. A couple of times I had mine closed but by snugging it tighter I could see a change.
Try using larger and fewer splits and don't let them get quite as fully engaged to minimize the offgassing that's feeding your cat. With this stove if you have a lot of fuel feeding the cat, its going to run hot.
I do not open the bypass when the stove gets hot, I just cut the air to 0 if needed.

 

In my experience and in my opinion, you should not have any 'air moving noises', including whistling, when the stove is completely shut down.

In the past, one person had a problem with some debris or burrs holding up the draft plates; you may want to get a mirror and a strong light and make sure you draft control plates are sitting flat on the bottom plate of the stove. If they are not, you will not be able to actually close the draft because air will flow around the lifted plated. And also as I think others have said, check the door gasket to make sure it is sealing well and the door is closing enough (there is a latch adjustment).

If the draft mechanism is OK and you still cannot throttle the stove back then installing a damper is exactly what I would recommend. Also, as others have said, new cats. are hyperactive and as cats. feed on smoke, cutting down a well- engaged load of splits can and often does actually make the cat. temp. climb even though the stove is actually going through the process of cooling down. After a little while, perhaps 5 to 15 minutes, the fire in the firebox will really slow down and finally slow down on smoke output and after that the cat. temps. will drop. Unfortunately, watching the cat. temp. and the stove top temp. are not good ways to see this happening; a firebox temperature measurement is best but a flue measurement is good also. Both will show the fire (the actual fire in the firebox) cooling down even as the cat. temp. goes up temporarily.

The I.S. is an excellent stove overall and once you get down the learning curve and get any potential bugs (actually pretty rare but they do happen) worked out, you will not have any trouble running this stove and I think will be quite pleased with it.

Brian

 

Thanks guys. The draft plates on the bottom are in good working order. I will try the dollar bill trick on the gaskets later, & I have triple checked the ash pan door the two times this happened. I will keep an eye on all of these & keep you posted. The whistling was coming through the secondary draft plate, as I could regulate the pitch by placing my finger over the opening...which really makes me think it's a strong draft. I called the friendly folks at Woodstock, & they recommended trying the damper install.

 

pa.forester, I think a key draft reducer is going to be your friend.., one word of advice get it and put it in NOW.... as Temps drop your draft will increase!

 

Well, for all the fact that it doesn't spill smoke and sucks floating ash in the door, I think the answer may still be not quite enough draft. Just 5 degrees colder outside the last two nights and I got these results (without using the ash pan door). The time formatting is stupid, so I added vertical grid lines for each hour. Ignore the labels at the bottom and just count an hour for each vertical line.



This was last night's. You can see that, 15 hours in, when I got up this morning it was still full of bigtime bright coals so I raked them together and dropped the ash through the grate. Opening the air all the way got me flames again and a 50F bump in STT before it finally used up all the fuel.

 

Oh, I also meant to ask, what would you guys consider the lowest cat probe temperature where the cat is still burning enough badness to protect the chimney against creosote formation even at lower flue temps?

 

I bet you will be just fine once the temperature hits 40 and even better when it hits the 30s. 50 is a little warm to fire it up but it's new and you wanted to use it. I don't light mine until the temperature dips below 50. At 49 I'm not not getting great draft but once the temperature gets to 45 I'm good to go. I don't technically need a fire at 49 but...well you know how it is.

 

Well once you are down to large hot coals later in the burn you likely aren't running with an active cat. However at that point you aren't producing creosote anyway.

 

The last two burns that have worked somewhat right have been lit between 40F and 45F. The problem is that the furnace starts needing to run about 55F. I'd like to keep it off as much as possible so the big chunk of change we put into the stove and install starts paying its keep.

So when is creosote formation a risk? I've read a bunch of the publications put out by various universities' ag extension offices, but they talk about not letting flue temps go below 250F (or 300F, or whatever they've tested) rather than talking about what phase of the burn cycle even has the possibility of producing creosote. I also wonder how cold my exhaust gasses are by the top of the stack because, measuring the outside wall of double-wall stove pipe, there's several hundred degrees of temp loss by the time the pipe gets to the ceiling. I'm curious if the gasses in the stove pipe are actually quite cold by the time they make it to the roofline.

 

There is no coorelation between the flue temp. and whether or not creosote is being formed, at least not with a cat. based stove (or a hybrid used in 'cat.' mode). The whole objective of efficiency with these stoves is to keep the firebox temps. as low as possible while 1) maintaining the fire of course and 2) having the overall stove (including the cat.) put out enough heat to maintain the building at a comfortale temp. So, when the stove is damped down and not allowed to burn hot (firebox), some or all of the wood smolders (pyrolyzes- like a cigarette without flame but a lot of smoke). This is exactly what the cat. thrives on; once ignited of 'lit- off', the cat. will burn all of that smoke and produce no creosote. Because the stove is quite efficient, this additional heat produced by the cat. is radiated into the room which leaves the exhaust gasses relatively cool. I try to run my I.S. with flue temps. no higher than 400F and usually around 350F, and that is internal (Easy Boys!) temp., not stove pipe wall temp.

So all those flue temp. gauges which show the various colors representing a 'dirty' or 'clean' burn just do not apply to modern cat. stoves. The key to clean running is to get the cat. lit- off and burning quickly and keep it going until all the materials that would make creosote are burned off, which is during the first 1/3 or 1/2 of the burn or so. Look at your own chart: notice the high cat. temps. that drop off sharply near the middle of the burn while the stove top temp. stays a lot more even? That is the cat. burning the creosote. The second half of the burn is actual carbon burning in the form of a charcoal fire and that does not produce any creosote.

These stoves can burn so clean that no chimney cleaning is needed for years although checking the chimney at least once a year is always a good idea. But mostly what is found in the chimney even after several years is just a bit of harmless brown dust.... and not very much of that either.

Not sure I have explained this well so please feel free to ask more questions, or the same questions again if I have done a really poor job....

Brian

 

So the short summary for someone in their freshman year is that the only "risk" period is on the way up because, by the time the temps are coming back down all the stuff that can form creosote is gone. To that end, just get the flue, and therefore cat, temp up as fast as possible to get the cat to light off and then don't worry about it.

Is that about right?

 

yup, I actually like to see my flue Temps low! try to give less heat to outdoors more in house! BDF actually has a modification I am thinking about drops flue Temps about 50 degrees! my first year with IS with marginal 6 cups of soot only creosote I had was at wire mesh on cap!